US20170138735A1 - Stable three-axis nuclear spin gyroscope - Google Patents
Stable three-axis nuclear spin gyroscope Download PDFInfo
- Publication number
- US20170138735A1 US20170138735A1 US15/218,401 US201615218401A US2017138735A1 US 20170138735 A1 US20170138735 A1 US 20170138735A1 US 201615218401 A US201615218401 A US 201615218401A US 2017138735 A1 US2017138735 A1 US 2017138735A1
- Authority
- US
- United States
- Prior art keywords
- canceled
- spin
- gyroscope
- nuclear
- centers
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C19/00—Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
- G01C19/58—Turn-sensitive devices without moving masses
- G01C19/60—Electronic or nuclear magnetic resonance gyrometers
- G01C19/62—Electronic or nuclear magnetic resonance gyrometers with optical pumping
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N24/00—Investigating or analyzing materials by the use of nuclear magnetic resonance, electron paramagnetic resonance or other spin effects
- G01N24/08—Investigating or analyzing materials by the use of nuclear magnetic resonance, electron paramagnetic resonance or other spin effects by using nuclear magnetic resonance
Definitions
- the invention related to the field of gyroscopes, and in particular a quantum-based gyroscope that provides a sensitive and stable three-axis gyroscope in the solid state.
- MEMS microelectromechanical systems
- an n-NV-based gyroscope includes a diamond structure implanted with a plurality of Nitrogen-Vacancy defect color centers in diamond (NV centers), whose nuclear spins form a spin gyroscope.
- a number of radio-frequency (rf) coils and microwave ( ⁇ w) co-planar waveguides are fabricated on the diamond structure to provide a sensitive and stable three-axis gyroscope in the solid state while achieving gyroscopic sensitivity by exploiting the coherence time of the 14 N nuclear spin associated with the NV centers in the diamond structure combined with the efficient optical polarization and measurement of electronic spin.
- a method of implementing a quantum sensor includes implanting a plurality of NV centers in a diamond structure, whose nuclear spins form a spin gyroscope. Moreover, the method includes fabricating a plurality of radio-frequency (rf) coils and microwave ( ⁇ w) co-planar waveguides on the diamond structure to provide a sensitive and stable three-axis gyroscope in the solid state while achieving gyroscopic sensitivity by exploiting the coherence time of the 14 N nuclear spin associated with the NV centers in the diamond structure combined with the efficient optical polarization and measurement of electronic spin.
- rf radio-frequency
- ⁇ w microwave
- a quantum sensor includes a diamond structure implanted with a plurality of NV centers, whose nuclear spins form a spin gyroscope.
- a number of radio-frequency (rf) coils and microwave ( ⁇ w) co-planar waveguides are fabricated on the diamond structure to provide a sensitive and stable three-axis gyroscope in the solid state while achieving gyroscopic sensitivity by exploiting the coherence time of the 14 N nuclear spin associated with the NV centers in the diamond structure combined with the efficient optical polarization and measurement of electronic spin.
- FIG. 1 is a schematic diagram illustrating an n-NV gyroscope formed in accordance with the invention
- FIG. 2 is a graph illustrating an n-NV-gyroscope control sequence
- FIG. 3 is a graph illustrating an n-NV-gyroscope sensitivity
- FIG. 4 is a graph illustrating the signal S c from the four classes of NV centers.
- FIGS. 5A-5B are schematic diagrams illustrating an integrated n-NV-MEMS gyroscope.
- the invention overcomes the drawbacks of current gyroscopes by using a solid-state spin associated with the nuclear spin of nitrogen-vacancy (NV) centers in diamond as a gyroscope (referred herein as n-NV gyro).
- n-NV gyro combines the efficient optical initialization and measurement offered by the NV-electronic spin with the stability and long coherence time of the nuclear spin, which is preserved even at high densities.
- FIG. 1 is a schematic diagram illustrating a n-NV gyro 2 formed in accordance with the invention.
- a slab of diamond 4 of dimensions (2.5 ⁇ 2.5) mm2 ⁇ 150 ⁇ m is anchored to the device body 6 .
- Radio-frequency (rf) coils and microwave ( ⁇ w) co-planar waveguides 8 are fabricated on the diamond 4 for fast control.
- NV centers are polarized by a green laser (532 nm) 10 , and state dependent fluorescence intensity (637 nm) is collected employing a side-collection technique.
- a second set of rf coils 12 rotate with respect to the diamond-chip frame, for example, by being attached to one or more rings 14 in a mechanical gimbal gyroscope.
- the 14 N nuclear spins are used as probes of the relative rotation between the diamond frame and the external rf-coil frame.
- the operating principles are based on the detection of the phase that the nitrogen-14 nuclear spin 1 ( 14 N) acquires when it rotates around its symmetry axis.
- b is a small magnetic field
- ⁇ Nb ⁇ Q is a small magnetic field
- the spin is subject to rf fields in the transverse plane at frequency Q and with a (gated) amplitude 2 ⁇ rf (t).
- the diamond rotates around the spin-symmetry axis (z axis) at a rate ⁇ with respect to the frame in which the rf field is applied.
- H rf 2 ⁇ rf (t)cos(Qt) ⁇ I x cos ( ⁇ t) ⁇ I y sin( ⁇ t) ⁇ .
- the second term (e ⁇ i ⁇ I z ) transforms H rf to
- n-NV-gyro operating principles are somewhat similar to NV-based magnetometers and NMR gyroscopes, some critical differences lead to its outstanding performance.
- magnetometry the sensitivity to rotation rates is independent of the spin's gyromagnetic ratio.
- 14 N nuclear spin as a sensor, leading to a much improved performance because of the isolation of nuclear spins from noise sources.
- this also requires new strategies for the polarization and readout of the nuclear spin.
- NMR-gyroscope designs use optical pumping for spin polarization the n-NV gyro exploits the unique properties of the NV electron spin for optical polarization and readout of the nuclear spins, achieving far better efficiencies, close to 100%. Furthermore, using a solid-state system allows the application of control fields in the same reference frame of the sensor spins, which, as shown below, decouple the spins from low-frequency noise sources, such as temperature fluctuations, stray magnetic fields, and strains. Stated equivalently, whereas NMR gyros are limited by the dephasing time T 2 * of the spins, the n-NV gyro is limited by the much longer coherence time T 2 .
- H en ⁇ S z 2 + ⁇ e bS z +QI z 2 +( ⁇ + ⁇ N b ) I z +A ⁇ right arrow over (S) ⁇ right arrow over (I) ⁇ (2)
- polarization transfer in the rotating frame does not lead to perfect polarization, unless the electronic spin is reduced to an effective spin 1 / 2 .
- the invention proposes using forbidden two-photon transitions to achieve population transfer. Driving the NV-electronic spin at the ⁇ e b+Q transitions with a field along its longitudinal (z) axis modulates its resonance frequency, thus, making energy exchange with the nuclear spin possible.
- the rf and ⁇ w pulses used for initialization and readout can be delivered by an on-chip circuit, integrated with the diamond.
- the NV-electronic spin is left in the
- a Ramsey sequence is applied using the off-chip rf driving, thus, inducing accumulation of a rotation-dependent phase [Eq. (1)].
- the sensor spin coherence time is limited by T 2 (and not by the shorter dephasing time T 2 *), which can be exceptionally long for nuclear spins.
- the additional pulse made possible by working with a solid-state device, is critical in making the n-NV gyro immune to a host of low-frequency drifts that limit the operational time of other gyroscope types.
- the n-NV gyro can operate at very high densities of the sensor spins. Ion implantation can reach an NV density of n-NV ⁇ 10 18 cm ⁇ 3 . Even assuming a density of residual single-nitrogen defects (P1 centers) n P1 ⁇ 10n-NV ⁇ 10 19 cm ⁇ 3 , the N T 2 time is not appreciably affected by the P1 bath. Indeed, while at these densities, the dipole-dipole interaction
- the N coherence time is also affected by the interaction with the close-by NV center, which induces dephasing when undergoing relaxation with T 1 ⁇ 2-6 ms at room temperature and low field.
- the echo sequence has the added benefit to make the measurement insensitive to many other imperfections, such as temperature variation, strain, background stray fields, variation in the quadrupolar interaction, and instability in the applied bias magnetic field.
- this scheme yields a solid-state gyroscope with stability comparable to that achieved in atomic systems.
- ⁇ ⁇ n ⁇ sin ⁇ ( ⁇ ⁇ ⁇ t ) 2 ⁇ ( ⁇ + ⁇ ⁇ ⁇ t ⁇ ⁇ - 1 ⁇ - ⁇ - ⁇ ⁇ ⁇ t ⁇ ⁇ + 1 ⁇ ) - cos ⁇ ( ⁇ ⁇ ⁇ t ) ⁇ ⁇ 0 ⁇ ( 3 )
- the readout sequence as shown in FIG. 2 , with pulses on resonance to both 0 ⁇ 1 transitions, generates the state
- ⁇ ⁇ en ⁇ 1 2 ⁇ sin ⁇ ( ⁇ ⁇ ⁇ t ) ⁇ [ ⁇ ⁇ ⁇ ⁇ t ⁇ ( ⁇ - 1 , - 1 ⁇ + ⁇ + 1 , - 1 ⁇ ) + ⁇ - ⁇ ⁇ ⁇ t ⁇ ( ⁇ + 1 , + 1 ⁇ + ⁇ - 1 , + 1 ⁇ ) - cos ⁇ ( ⁇ ⁇ ⁇ t ) ⁇ ⁇ 0 , 0 ⁇ ] ( 4 )
- Optical readout extracts the information about the rotation ⁇ .
- the measurement step can be repeated to improve the contrast.
- the higher detection efficiency will also allow a large dynamic range by exploiting adaptive phase-estimation schemes.
- the sensitivity per unit time ⁇ is ideally shot-noise limited: ⁇ 1/ ⁇ square root over (tN) ⁇ , where N is the number of nitrogen nuclear spins associated with NV centers in the diamond chip.
- the estimated sensitivity for the n-NV gyro is then ⁇ 0.5 (mdegs ⁇ 1 )/ ⁇ square root over (Hz) ⁇ , better than the current MEMS gyroscopes, although in a slightly larger volume, as shown in FIG. 3 .
- the stability of the n-NV gyro can be much higher than for MEMS and can be comparable to atomic gyroscopes, shown in FIG. 4 .
- the echo-based scheme makes the n-NV gyro insensitive to drifts due to strain, temperature, and stray fields.
- the NV spin is a sensitive probe of these effects, capable of measuring magnetic and electric fields as well as frequency and temperature shifts. Because of almost 4 orders of magnitude larger sensitivity of the NV spin than the 14 N spin (given by the ratio ⁇ e / ⁇ N ), the NV can be used to monitor such drifts and to correct them via a feedback mechanism.
- the NV center in diamond includes a substitutional nitrogen adjacent to a vacancy in the lattice.
- the nitrogen to-vacancy axis sets the direction of the electronic zero-field splitting and nuclear quadrupolar interaction.
- the axis can be along any of the four tetrahedral 1,1,1 crystallographic directions of the diamond lattice. This intrinsic symmetry can be exploited to operate the n-NV gyro as a three-axis gyroscope, extracting information about the rotation rate as well as its direction.
- the 14 N still undergoes a complex evolution that depends on ⁇ right arrow over ( ⁇ ) ⁇ .
- tan ⁇ ( ⁇ 2 1 ) sin 2 ⁇ ( ⁇ ) ⁇ sin ⁇ ( 2 ⁇ ⁇ ⁇ ) ⁇ sin 2 ⁇ ( ⁇ ⁇ ⁇ t / 2 ) + cos ⁇ ( ⁇ ) ⁇ sin ⁇ ( ⁇ ⁇ ⁇ t ) cos ⁇ ( ⁇ ⁇ ⁇ t ) - sin 2 ⁇ ( ⁇ ) ⁇ cos 2 ⁇ ( ⁇ ) ⁇ cos ⁇ ( ⁇ ⁇ ⁇ t ) + sin 2 ⁇ ( ⁇ ) ⁇ cos 2 ⁇ ( ⁇ ) ( 6 )
- ⁇ ⁇ n ⁇ ⁇ - ⁇ 2 ⁇ [ sin ⁇ ( ⁇ 2 ) - ⁇ cos ⁇ ( ⁇ 2 2 ) ⁇ cos ⁇ ( ⁇ 2 ) ] 2 ⁇ ⁇ + 1 ⁇ - sin ⁇ ( ⁇ 2 2 ) ⁇ cos ⁇ ( ⁇ 2 ) ⁇ ⁇ 0 ⁇ - ⁇ ⁇ 2 ⁇ [ sin ⁇ ( ⁇ 2 ) + ⁇ cos ⁇ ( ⁇ 2 2 ) ⁇ cos ⁇ ( ⁇ 2 ) ] 2 ⁇ ⁇ - : ( 7 )
- the signal can be measured by sequentially mapping the nuclear-spin state onto the corresponding electronic spin via on resonance microwave pulses (a bias field of 10-20 G is sufficient to lift the frequency degeneracy among the four classes).
- a more efficient scheme would take advantage of repeated readouts and long relaxation times of the nuclear spins to measure the signal from three NV classes without the need to repeat the preparation and echo sequences.
- a driving field along a single direction makes the deconvolution algorithm more complex, the signal arising from three classes of NV centers is still enough to reconstruct the rotation rate and its direction.
- the invention proposes a solid-state device able to measure rotation rates with a resolution of ⁇ 0.5 (mdegs ⁇ 1 )/ ⁇ square root over (Hz) ⁇ in a 1-mm 3 package while providing great stability.
- the device performance compares favorably with respect to other current.
- FIG. 5A shows an integrated n-NVMEMS gyroscope 22 , comprising a bulk acoustic wave (BAW) single-axis MEMS gyroscope 20 in an 800- ⁇ m diamond disk 24 implanted with NV centers, whose nuclear spins form a spin gyroscope.
- the spins implanted in the disk are polarized by a laser 26 .
- the electrodes 30 surrounding the disk 24 are silvered to allow for total internal reflection, and fluorescence is side collected by replacing one of them by an on-chip optical waveguide 32 at 638 nm. Strip lines 38 for rf or ⁇ w control are fabricated on the disk.
- FIG. 5B shows the operation of the BAW mechanical gyroscope 20 .
- the BAW 20 is electrostatically driven in the second elliptic mode by a ⁇ 10-kHz sinusoidal signal from the drive electrodes 28 .
- a rotation out of the plane causes a decrease in the gap near the sense electrodes 36 , leading to a capacitive measurement of the rotation.
- Combinatoric filtering with the n-NV measurement leads to noise rejection and improved stability.
- High-performance MEMS gyroscopes can be fabricated in diamond using reactive ion-etching tools. While the substrate itself acts as a mechanical gyroscope, the nuclear spins inside it act as a spin gyroscope. These two gyroscopes, employing complementary physical effects, are sensitive to different sources of noise, which can be corrected by Kalman-filter techniques. The integrated device would offer both stability and sensitivity in a small package.
- the invention introduces a quantum sensor that provides a sensitive and stable three-axis gyroscope in the solid state.
- One can achieve high sensitivity by exploiting the long coherence time of the 14 N nuclear spin associated with the nitrogen-vacancy center in diamond, combined with the efficient polarization and measurement of its electronic spin.
- the gyroscope is based on a simple Ramsey interferometry scheme, one can use coherent control of the quantum sensor to improve its coherence time and robustness against long-time drifts.
- Such a sensor can achieve a sensitivity of ⁇ ⁇ 0.5 (mdeg s ⁇ 1 )/ ⁇ square root over (Hzmm 3 ) ⁇ while offering enhanced stability in a small footprint.
- we exploit the four axes of delocalization of the nitrogen-vacancy center to measure not only the rate of rotation, but also its direction, thus obtaining a compact three-axis gyroscope.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- High Energy & Nuclear Physics (AREA)
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Gyroscopes (AREA)
Abstract
An n-NV-based gyroscope is provided that includes a diamond structure implanted with a plurality of NV centers, whose nuclear spins form a spin gyroscope. A number of radio-frequency (rf) coils and microwave (μw) co-planar waveguides are fabricated on the diamond structure to provide a sensitive and stable three-axis gyroscope in the solid state while achieving gyroscopic sensitivity by exploiting the coherence time of the 14N nuclear spin associated with the NV centers in the diamond structure combined with the efficient optical polarization and measurement of electronic spin.
Description
- This invention was made with government support under Contract No. W911NF-11-1-0400 awarded by the Army Research Office. The government has certain rights in the invention
- The invention related to the field of gyroscopes, and in particular a quantum-based gyroscope that provides a sensitive and stable three-axis gyroscope in the solid state.
- Conventional commercial gyroscopes are built using microelectromechanical systems (MEMS) technology that allows for sensitivities exceeding 3 (mdeg s−1)/√{square root over (Hz)} in a hundreds of micron-sized footprint. Despite several advantages—including low current drives (˜100 μA) and large bandwidths (200 deg/s)—that have allowed MEMS gyroscopes to gain ubiquitous usage, they suffer from one critical drawback: The sensitivity drifts after a few minutes of operation, making them unattractive for geodetic applications. The intrinsic reason for these drifts formation of charged asperities at the surface of the capacitive transduction mechanism is endemic to MEMS but does not occur in other systems used as gyroscopes, such as atom interferometers or nuclear spins. However, to achieve sensitivities comparable to MEMS, these systems require large volumes (˜cm3), long startup times, and large power and space overheads for excitation and detection.
- According to one aspect of the invention, there is provided an n-NV-based gyroscope. The n-NV-based gyroscope includes a diamond structure implanted with a plurality of Nitrogen-Vacancy defect color centers in diamond (NV centers), whose nuclear spins form a spin gyroscope. A number of radio-frequency (rf) coils and microwave (μw) co-planar waveguides are fabricated on the diamond structure to provide a sensitive and stable three-axis gyroscope in the solid state while achieving gyroscopic sensitivity by exploiting the coherence time of the 14N nuclear spin associated with the NV centers in the diamond structure combined with the efficient optical polarization and measurement of electronic spin.
- According to another aspect of the invention, there is provided a method of implementing a quantum sensor. The method includes implanting a plurality of NV centers in a diamond structure, whose nuclear spins form a spin gyroscope. Moreover, the method includes fabricating a plurality of radio-frequency (rf) coils and microwave (μw) co-planar waveguides on the diamond structure to provide a sensitive and stable three-axis gyroscope in the solid state while achieving gyroscopic sensitivity by exploiting the coherence time of the 14N nuclear spin associated with the NV centers in the diamond structure combined with the efficient optical polarization and measurement of electronic spin.
- According to another aspect of the invention, there is provided a quantum sensor. The quantum sensor includes a diamond structure implanted with a plurality of NV centers, whose nuclear spins form a spin gyroscope. A number of radio-frequency (rf) coils and microwave (μw) co-planar waveguides are fabricated on the diamond structure to provide a sensitive and stable three-axis gyroscope in the solid state while achieving gyroscopic sensitivity by exploiting the coherence time of the 14N nuclear spin associated with the NV centers in the diamond structure combined with the efficient optical polarization and measurement of electronic spin.
-
FIG. 1 is a schematic diagram illustrating an n-NV gyroscope formed in accordance with the invention; -
FIG. 2 is a graph illustrating an n-NV-gyroscope control sequence; -
FIG. 3 is a graph illustrating an n-NV-gyroscope sensitivity -
FIG. 4 is a graph illustrating the signal Sc from the four classes of NV centers; and -
FIGS. 5A-5B are schematic diagrams illustrating an integrated n-NV-MEMS gyroscope. - The invention overcomes the drawbacks of current gyroscopes by using a solid-state spin associated with the nuclear spin of nitrogen-vacancy (NV) centers in diamond as a gyroscope (referred herein as n-NV gyro). The n-NV gyro combines the efficient optical initialization and measurement offered by the NV-electronic spin with the stability and long coherence time of the nuclear spin, which is preserved even at high densities.
-
FIG. 1 is a schematic diagram illustrating a n-NV gyro 2 formed in accordance with the invention. A slab ofdiamond 4 of dimensions (2.5×2.5) mm2×150 μm is anchored to thedevice body 6. Radio-frequency (rf) coils and microwave (μw)co-planar waveguides 8 are fabricated on thediamond 4 for fast control. NV centers are polarized by a green laser (532 nm) 10, and state dependent fluorescence intensity (637 nm) is collected employing a side-collection technique. A second set ofrf coils 12 rotate with respect to the diamond-chip frame, for example, by being attached to one ormore rings 14 in a mechanical gimbal gyroscope. The 14N nuclear spins are used as probes of the relative rotation between the diamond frame and the external rf-coil frame. - The operating principles are based on the detection of the phase that the nitrogen-14 nuclear spin 1 (14N) acquires when it rotates around its symmetry axis. Consider an
isolated spin 1 with Hamiltonian H0=QI2+γNbIZ, where Q is the intrinsic quadrupolar interaction (Q=−4.95 MHz for the NV center's 14N), b is a small magnetic field, γNb<<Q, and γN=2π×3.1 MHz/T is the 14N gyromagnetic ratio. The spin is subject to rf fields in the transverse plane at frequency Q and with a (gated) amplitude 2ωrf(t). The diamond rotates around the spin-symmetry axis (z axis) at a rate Ω with respect to the frame in which the rf field is applied. Thus, the driving field is described by the Hamiltonian Hrf=2ωrf(t)cos(Qt)└Ix cos (Ωt)−Iy sin(Ωt)┘. One can describe the spin evolution in the interaction frame set by (QIz 2−ωIZ). The second term (e−iΩIz ) transforms Hrf to -
2ωrf cos(Qt)I x=ωrf └e −iQIz 2 t I x e iQIz 2 t +e iQIz 2 t I x e −iQIz 2 t┘ (1) - In a Ramsey sequence shown in
FIG. 2 , the spin acquires a phase φ=(γNb+Ω)t from which one can extract the rotation rate. Although the n-NV-gyro operating principles are somewhat similar to NV-based magnetometers and NMR gyroscopes, some critical differences lead to its outstanding performance. In contrast to magnetometry, the sensitivity to rotation rates is independent of the spin's gyromagnetic ratio. Thus, one can exploit the 14N nuclear spin as a sensor, leading to a much improved performance because of the isolation of nuclear spins from noise sources. However, this also requires new strategies for the polarization and readout of the nuclear spin. There are two critical advantages of the n-NV gyro with respect to NMR gyros. - Although certain NMR-gyroscope designs use optical pumping for spin polarization the n-NV gyro exploits the unique properties of the NV electron spin for optical polarization and readout of the nuclear spins, achieving far better efficiencies, close to 100%. Furthermore, using a solid-state system allows the application of control fields in the same reference frame of the sensor spins, which, as shown below, decouple the spins from low-frequency noise sources, such as temperature fluctuations, stray magnetic fields, and strains. Stated equivalently, whereas NMR gyros are limited by the dephasing time T2* of the spins, the n-NV gyro is limited by the much longer coherence time T2.
- Consider first the operation of a one-axis n-NV gyro. The nuclear spin is first initialized by polarization transfer from the electronic NV spin. Under optical excitation, the electronic ms=±1 levels follow a non-spin-preserving transition through metastable levels down to the ms=0 ground state, yielding high polarization of the electronic spin. The polarization can be transferred to the nuclear spin exploiting the hyperfine coupling A=2.2 MHz in the electron-nuclear-spin Hamiltonian,
-
H en =ΔS z 2+γe bS z +QI z 2+(Ω+γN b)I z +A{right arrow over (S)}·{right arrow over (I)} (2) - where γe=2.8 MHz/G is the electronic gyromagnetic ratio and Δ=2.87 GHz is the zero-field splitting.
- Several techniques for polarization transfer have been implemented experimentally, including measurement post selection and exploiting a level anticrossing in the orbital excited state at b˜500 G (using an adiabatic passage or the resonance between the nuclear and the electronic spins). Unfortunately, all these techniques have drawbacks that make them unsuitable for purposes of the invention. The first technique is too lengthy, whereas the second prevents the use of repeated readouts and requires precise alignment of a large static magnetic field. At low field, polarization transfer between the electronic and the nuclear spins is complicated by the fact that both are
spin 1. - Unlike for
spin 1/2, polarization transfer in the rotating frame (under the Hartmann-Hahn-matching condition) does not lead to perfect polarization, unless the electronic spin is reduced to aneffective spin 1/2. Instead, the invention proposes using forbidden two-photon transitions to achieve population transfer. Driving the NV-electronic spin at the Δ±γeb+Q transitions with a field along its longitudinal (z) axis modulates its resonance frequency, thus, making energy exchange with the nuclear spin possible. - Although the transition rates are usually small, the ability to drive the NV-electronic spin with very high fields makes the polarization time
-
- short. For a Rabi frequency=500 MHz and a field b=20 G, the time required is only 1.3 μs. This initialization time is far shorter than for other gyroscope types, including the few tens of milliseconds of startup time required for MEMS gyroscopes.
- For ease of operation, one can assume that the rf and μw pulses used for initialization and readout can be delivered by an on-chip circuit, integrated with the diamond. After preparation, the NV-electronic spin is left in the |0state, which does not couple to the 14N nuclear spin nor to the spin bath. A Ramsey sequence is applied using the off-chip rf driving, thus, inducing accumulation of a rotation-dependent phase [Eq. (1)]. A 2π pulse at the center of the sequence, applied with the on-chip rf field, refocuses the effects of stray magnetic fields and provides decoupling from the spin bath. The sensor spin coherence time is limited by T2 (and not by the shorter dephasing time T2*), which can be exceptionally long for nuclear spins. Thus, the additional pulse, made possible by working with a solid-state device, is critical in making the n-NV gyro immune to a host of low-frequency drifts that limit the operational time of other gyroscope types.
- Moreover, since the echo refocuses the coupling to other electronic spins, the n-NV gyro can operate at very high densities of the sensor spins. Ion implantation can reach an NV density of n-NV˜1018 cm−3. Even assuming a density of residual single-nitrogen defects (P1 centers) nP1≈10n-NV˜1019 cm−3, the N T2 time is not appreciably affected by the P1 bath. Indeed, while at these densities, the dipole-dipole interaction
-
-
- This leads to motional narrowing and a very slow exponential decay as confirmed by simulations.
- The N coherence time is also affected by the interaction with the close-by NV center, which induces dephasing when undergoing relaxation with T1˜2-6 ms at room temperature and low field. Whereas, in high-purity diamonds, the dephasing time T2* can be as long as 7 ms, in the proposed conditions of operation, one can conservatively estimate the coherence time of the nuclear spin to be T2=1 ms. The echo sequence has the added benefit to make the measurement insensitive to many other imperfections, such as temperature variation, strain, background stray fields, variation in the quadrupolar interaction, and instability in the applied bias magnetic field. Thus, this scheme yields a solid-state gyroscope with stability comparable to that achieved in atomic systems.
- After the sensing sequence, the 14N spin is left in the state,
-
- which can be mapped into a population difference between the NV levels thanks to the hyperfine coupling (here, one only considers the longitudinal component of the isotropic hyperfine interaction AIZSZ because of the large zero-field splitting Δ).
-
-
- where |mz S,mz I indicates an eigenstate of SZ and IZ for the electronic and nuclear spins, respectively. The time required to map the state onto the NV center is tmap=230 ns, which is close to the T2* time for the NV at high densities, thus, one can expect a reduction in contrast. Indeed, it is the NV dephasing time that ultimately limits the allowed spin densities. A possible solution would be to perform a spin echo on both nuclear and electronic spins to extend the coherence time.
- Optical readout extracts the information about the rotation Ω. The measurement step can be repeated to improve the contrast. Although, at low field, the nuclear-spin relaxation time under optical illumination is relatively short, thus, limiting the number of repeated readouts when combined with a side-collection scheme giving high collection efficiency ηm≈1, one can still achieve a detection efficiency of C˜0.25 for nr=100 repetitions and a total readout time of tm≈150 μs. The higher detection efficiency will also allow a large dynamic range by exploiting adaptive phase-estimation schemes.
- One can now consider the performance of the n-NV-gyroscope design with respect to sensitivity and stability and its potential advantages over competing technologies.
- The sensitivity per unit time η is ideally shot-noise limited: η∝1/√{square root over (tN)}, where N is the number of nitrogen nuclear spins associated with NV centers in the diamond chip. The expected sensitivity can be estimated by limiting the interrogation time t to T2 and taking into consideration the preparation and readout dead times td=tpol+tro and the detection efficiency C,
-
- For a volume V=1 mm3, containing N=n-NVV/4≈2.5×1014 sensor spins along the rotation axis, the estimated sensitivity for the n-NV gyro is then η≈0.5 (mdegs−1)/√{square root over (Hz)}, better than the current MEMS gyroscopes, although in a slightly larger volume, as shown in
FIG. 3 . - More importantly, the stability of the n-NV gyro can be much higher than for MEMS and can be comparable to atomic gyroscopes, shown in
FIG. 4 . Indeed, the echo-based scheme makes the n-NV gyro insensitive to drifts due to strain, temperature, and stray fields. In addition, the NV spin is a sensitive probe of these effects, capable of measuring magnetic and electric fields as well as frequency and temperature shifts. Because of almost 4 orders of magnitude larger sensitivity of the NV spin than the 14N spin (given by the ratio γe/γN), the NV can be used to monitor such drifts and to correct them via a feedback mechanism. - The NV center in diamond includes a substitutional nitrogen adjacent to a vacancy in the lattice. The nitrogen to-vacancy axis sets the direction of the electronic zero-field splitting and nuclear quadrupolar interaction. The axis can be along any of the four tetrahedral 1,1,1 crystallographic directions of the diamond lattice. This intrinsic symmetry can be exploited to operate the n-NV gyro as a three-axis gyroscope, extracting information about the rotation rate as well as its direction.
- Although the maximum sensitivity is achieved for rotations aligned with the symmetry axis, if the rotation is about an axis forming an angle {θ,φ} with respect to the NV axis, the 14N still undergoes a complex evolution that depends on {right arrow over (Ω)}. The two rf pulses in the Ramsey interferometry scheme differ not only by their phase ψ1,2 in the NV x-y plane, but also by their flip angle α1,2. If one can assume the first pulse to be along the x axis for the first NV class, the second rf pulse is rotated by an angle ψ1,2=ψ(θ,φ,Ωt) in the NV x-y plane with
-
- The flip angle α1,2=α(θ,φ,Ωt) is also reduced with respect to the nominal angle π,
- The state at the end of the Ramsey sequence is then given by
-
- from which one can extract information about the rotation rate Ω. Similar expressions hold for the other NV classes if it is possible to drive excitation fields in the transverse plane of each family. Then, the angles α2 c, ψ2 c are different for each family of NVs, and measuring the signal from three families allows extracting information about {right arrow over (Ω)}.
- Assuming that the driving field is applied only along one direction for all the four NV classes, even the first excitation pulse angles {ψ1 c, α1 c} differ for each class, whereas, for the second pulse, {ψ2 c, α2 c} depend not only on the class, but also on the rotation vector {right arrow over (Ω)} via simple trigonometric relationships. The signal for each class is defined as,
-
S c=[cos(α1 c/2)cos(α2 c/2)−sin(α1 c/2)sin(α2 c/2)cos(ψ1 c−ψ2 c)]2 (8) - which is shown in
FIG. 4 . The signal can be measured by sequentially mapping the nuclear-spin state onto the corresponding electronic spin via on resonance microwave pulses (a bias field of 10-20 G is sufficient to lift the frequency degeneracy among the four classes). A more efficient scheme would take advantage of repeated readouts and long relaxation times of the nuclear spins to measure the signal from three NV classes without the need to repeat the preparation and echo sequences. Although a driving field along a single direction makes the deconvolution algorithm more complex, the signal arising from three classes of NV centers is still enough to reconstruct the rotation rate and its direction. - The invention proposes a solid-state device able to measure rotation rates with a resolution of η≈0.5 (mdegs−1)/√{square root over (Hz)} in a 1-mm3 package while providing great stability. The device performance compares favorably with respect to other current. Even smaller devices—on the micron scale—could be useful by exploiting this long-time stability to improve the performance of the MEMS gyroscope in a combinatoric device, as shown in
FIGS. 5A-5B . - In particular,
FIG. 5A shows an integrated n-NVMEMS gyroscope 22, comprising a bulk acoustic wave (BAW) single-axis MEMS gyroscope 20 in an 800-μm diamond disk 24 implanted with NV centers, whose nuclear spins form a spin gyroscope. The spins implanted in the disk are polarized by alaser 26. Theelectrodes 30 surrounding thedisk 24 are silvered to allow for total internal reflection, and fluorescence is side collected by replacing one of them by an on-chipoptical waveguide 32 at 638 nm. Strip lines 38 for rf or μw control are fabricated on the disk.FIG. 5B shows the operation of the BAWmechanical gyroscope 20. TheBAW 20 is electrostatically driven in the second elliptic mode by a ˜10-kHz sinusoidal signal from thedrive electrodes 28. - A rotation out of the plane causes a decrease in the gap near the
sense electrodes 36, leading to a capacitive measurement of the rotation. Combinatoric filtering with the n-NV measurement leads to noise rejection and improved stability. High-performance MEMS gyroscopes can be fabricated in diamond using reactive ion-etching tools. While the substrate itself acts as a mechanical gyroscope, the nuclear spins inside it act as a spin gyroscope. These two gyroscopes, employing complementary physical effects, are sensitive to different sources of noise, which can be corrected by Kalman-filter techniques. The integrated device would offer both stability and sensitivity in a small package. - The invention introduces a quantum sensor that provides a sensitive and stable three-axis gyroscope in the solid state. One can achieve high sensitivity by exploiting the long coherence time of the 14N nuclear spin associated with the nitrogen-vacancy center in diamond, combined with the efficient polarization and measurement of its electronic spin. Although the gyroscope is based on a simple Ramsey interferometry scheme, one can use coherent control of the quantum sensor to improve its coherence time and robustness against long-time drifts. Such a sensor can achieve a sensitivity of η˜0.5 (mdeg s−1)/√{square root over (Hzmm3)} while offering enhanced stability in a small footprint. In addition, we exploit the four axes of delocalization of the nitrogen-vacancy center to measure not only the rate of rotation, but also its direction, thus obtaining a compact three-axis gyroscope.
- Although the present invention has been shown and described with respect to several preferred embodiments thereof, Various changes, omissions and additions to the form and detail thereof, may be made therein, without departing from the spirit and scope of the invention.
Claims (33)
1. An n-NV-based gyroscope comprising:
a diamond structure implanted with a plurality of NV centers, whose nuclear spins form a spin gyroscope; and
a plurality of radio-frequency (rf) coils and microwave (μw) co-planar waveguides being fabricated on the diamond structure to provide a sensitive and stable three-axis gyroscope in the solid state while achieving gyroscopic sensitivity by exploiting the coherence time of the nuclear spin associated with the NV centers in the diamond structure combined with the efficient optical polarization and measurement of electronic spin.
2. (canceled)
3. (canceled)
4. (canceled)
5. (canceled)
6. (canceled)
7. (canceled)
8. (canceled)
9. (canceled)
10. (canceled)
11. (canceled)
12. (canceled)
13. (canceled)
14. (canceled)
15. (canceled)
16. (canceled)
17. (canceled)
18. (canceled)
19. (canceled)
20. (canceled)
21. (canceled)
22. (canceled)
23. (canceled)
24. (canceled)
25. (canceled)
26. (canceled)
27. (canceled)
28. (canceled)
29. (canceled)
30. (canceled)
31. (canceled)
32. (canceled)
33. (canceled)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US15/218,401 US20170138735A1 (en) | 2013-05-01 | 2016-07-25 | Stable three-axis nuclear spin gyroscope |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/874,718 US9417068B2 (en) | 2013-05-01 | 2013-05-01 | Stable three-axis nuclear spin gyroscope |
US15/218,401 US20170138735A1 (en) | 2013-05-01 | 2016-07-25 | Stable three-axis nuclear spin gyroscope |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/874,718 Continuation US9417068B2 (en) | 2013-05-01 | 2013-05-01 | Stable three-axis nuclear spin gyroscope |
Publications (1)
Publication Number | Publication Date |
---|---|
US20170138735A1 true US20170138735A1 (en) | 2017-05-18 |
Family
ID=51841129
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/874,718 Active 2035-05-05 US9417068B2 (en) | 2013-05-01 | 2013-05-01 | Stable three-axis nuclear spin gyroscope |
US15/218,401 Abandoned US20170138735A1 (en) | 2013-05-01 | 2016-07-25 | Stable three-axis nuclear spin gyroscope |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/874,718 Active 2035-05-05 US9417068B2 (en) | 2013-05-01 | 2013-05-01 | Stable three-axis nuclear spin gyroscope |
Country Status (1)
Country | Link |
---|---|
US (2) | US9417068B2 (en) |
Cited By (35)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20160146904A1 (en) * | 2014-09-25 | 2016-05-26 | Lockheed Martin Corporation | Micro-dnv device |
US10006973B2 (en) | 2016-01-21 | 2018-06-26 | Lockheed Martin Corporation | Magnetometer with a light emitting diode |
US10012704B2 (en) | 2015-11-04 | 2018-07-03 | Lockheed Martin Corporation | Magnetic low-pass filter |
US10088336B2 (en) | 2016-01-21 | 2018-10-02 | Lockheed Martin Corporation | Diamond nitrogen vacancy sensed ferro-fluid hydrophone |
US10088452B2 (en) | 2016-01-12 | 2018-10-02 | Lockheed Martin Corporation | Method for detecting defects in conductive materials based on differences in magnetic field characteristics measured along the conductive materials |
US10120039B2 (en) | 2015-11-20 | 2018-11-06 | Lockheed Martin Corporation | Apparatus and method for closed loop processing for a magnetic detection system |
US10126377B2 (en) | 2016-05-31 | 2018-11-13 | Lockheed Martin Corporation | Magneto-optical defect center magnetometer |
US10228429B2 (en) | 2017-03-24 | 2019-03-12 | Lockheed Martin Corporation | Apparatus and method for resonance magneto-optical defect center material pulsed mode referencing |
US10241158B2 (en) | 2015-02-04 | 2019-03-26 | Lockheed Martin Corporation | Apparatus and method for estimating absolute axes' orientations for a magnetic detection system |
US10274550B2 (en) | 2017-03-24 | 2019-04-30 | Lockheed Martin Corporation | High speed sequential cancellation for pulsed mode |
US10277208B2 (en) | 2014-04-07 | 2019-04-30 | Lockheed Martin Corporation | Energy efficient controlled magnetic field generator circuit |
US10281550B2 (en) | 2016-11-14 | 2019-05-07 | Lockheed Martin Corporation | Spin relaxometry based molecular sequencing |
US10317279B2 (en) | 2016-05-31 | 2019-06-11 | Lockheed Martin Corporation | Optical filtration system for diamond material with nitrogen vacancy centers |
US10333588B2 (en) | 2015-12-01 | 2019-06-25 | Lockheed Martin Corporation | Communication via a magnio |
US10330744B2 (en) | 2017-03-24 | 2019-06-25 | Lockheed Martin Corporation | Magnetometer with a waveguide |
US10338162B2 (en) | 2016-01-21 | 2019-07-02 | Lockheed Martin Corporation | AC vector magnetic anomaly detection with diamond nitrogen vacancies |
US10338164B2 (en) | 2017-03-24 | 2019-07-02 | Lockheed Martin Corporation | Vacancy center material with highly efficient RF excitation |
US10338163B2 (en) | 2016-07-11 | 2019-07-02 | Lockheed Martin Corporation | Multi-frequency excitation schemes for high sensitivity magnetometry measurement with drift error compensation |
US10345395B2 (en) | 2016-12-12 | 2019-07-09 | Lockheed Martin Corporation | Vector magnetometry localization of subsurface liquids |
US10345396B2 (en) | 2016-05-31 | 2019-07-09 | Lockheed Martin Corporation | Selected volume continuous illumination magnetometer |
US10359479B2 (en) | 2017-02-20 | 2019-07-23 | Lockheed Martin Corporation | Efficient thermal drift compensation in DNV vector magnetometry |
US10371765B2 (en) | 2016-07-11 | 2019-08-06 | Lockheed Martin Corporation | Geolocation of magnetic sources using vector magnetometer sensors |
US10371760B2 (en) | 2017-03-24 | 2019-08-06 | Lockheed Martin Corporation | Standing-wave radio frequency exciter |
US10379174B2 (en) | 2017-03-24 | 2019-08-13 | Lockheed Martin Corporation | Bias magnet array for magnetometer |
US10408889B2 (en) | 2015-02-04 | 2019-09-10 | Lockheed Martin Corporation | Apparatus and method for recovery of three dimensional magnetic field from a magnetic detection system |
US10408890B2 (en) | 2017-03-24 | 2019-09-10 | Lockheed Martin Corporation | Pulsed RF methods for optimization of CW measurements |
US10459041B2 (en) | 2017-03-24 | 2019-10-29 | Lockheed Martin Corporation | Magnetic detection system with highly integrated diamond nitrogen vacancy sensor |
US10466312B2 (en) | 2015-01-23 | 2019-11-05 | Lockheed Martin Corporation | Methods for detecting a magnetic field acting on a magneto-optical detect center having pulsed excitation |
CN110600880A (en) * | 2019-09-19 | 2019-12-20 | 北京航空航天大学 | Circularly polarized frequency-adjustable solid color center microwave control system and method without phase shifter |
US10520558B2 (en) | 2016-01-21 | 2019-12-31 | Lockheed Martin Corporation | Diamond nitrogen vacancy sensor with nitrogen-vacancy center diamond located between dual RF sources |
US10527746B2 (en) | 2016-05-31 | 2020-01-07 | Lockheed Martin Corporation | Array of UAVS with magnetometers |
US10571530B2 (en) | 2016-05-31 | 2020-02-25 | Lockheed Martin Corporation | Buoy array of magnetometers |
CN111077581A (en) * | 2019-05-17 | 2020-04-28 | 吉林大学 | Tunnel water inrush three-dimensional nuclear magnetic resonance advanced detection device and imaging method |
US10677953B2 (en) | 2016-05-31 | 2020-06-09 | Lockheed Martin Corporation | Magneto-optical detecting apparatus and methods |
US10725124B2 (en) | 2014-03-20 | 2020-07-28 | Lockheed Martin Corporation | DNV magnetic field detector |
Families Citing this family (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9417068B2 (en) * | 2013-05-01 | 2016-08-16 | Massachusetts Institute Of Technology | Stable three-axis nuclear spin gyroscope |
US9638821B2 (en) | 2014-03-20 | 2017-05-02 | Lockheed Martin Corporation | Mapping and monitoring of hydraulic fractures using vector magnetometers |
US9910104B2 (en) | 2015-01-23 | 2018-03-06 | Lockheed Martin Corporation | DNV magnetic field detector |
US9853837B2 (en) | 2014-04-07 | 2017-12-26 | Lockheed Martin Corporation | High bit-rate magnetic communication |
EP3248022A4 (en) * | 2015-01-23 | 2018-12-05 | Lockheed Martin Corporation | Apparatus and method for high sensitivity magnetometry measurement and signal processing in a magnetic detection system |
CA2975103A1 (en) | 2015-01-28 | 2016-08-04 | Stephen M. SEKELSKY | In-situ power charging |
WO2016190909A2 (en) | 2015-01-28 | 2016-12-01 | Lockheed Martin Corporation | Magnetic navigation methods and systems utilizing power grid and communication network |
CN104697512B (en) * | 2015-03-20 | 2017-10-03 | 中国科学技术大学 | A kind of diamond colour center gyroscope and method for measuring angular velocity based on Aharonov Anandan geometry phases |
CN105444749B (en) * | 2015-11-07 | 2018-02-02 | 中北大学 | Cluster NV colour center diamond solid-state spin resonance gyroscopes based on Baily phase shift |
WO2017087014A1 (en) * | 2015-11-20 | 2017-05-26 | Lockheed Martin Corporation | Apparatus and method for hypersensitivity detection of magnetic field |
CN105403210B (en) * | 2015-12-24 | 2018-04-06 | 北京航空航天大学 | A kind of microminiature single shaft diamond gyro |
WO2017127094A1 (en) | 2016-01-21 | 2017-07-27 | Lockheed Martin Corporation | Magnetometer with light pipe |
WO2017127081A1 (en) | 2016-01-21 | 2017-07-27 | Lockheed Martin Corporation | Diamond nitrogen vacancy sensor with circuitry on diamond |
GB2562193B (en) | 2016-01-21 | 2021-12-22 | Lockheed Corp | Diamond nitrogen vacancy sensor with common RF and magnetic fields generator |
WO2017127090A1 (en) | 2016-01-21 | 2017-07-27 | Lockheed Martin Corporation | Higher magnetic sensitivity through fluorescence manipulation by phonon spectrum control |
US10145910B2 (en) | 2017-03-24 | 2018-12-04 | Lockheed Martin Corporation | Photodetector circuit saturation mitigation for magneto-optical high intensity pulses |
CN106441262B (en) * | 2016-07-11 | 2023-04-07 | 中北大学 | Non-exchange quantum geometric phase NV color center gyroscope |
RU2661442C2 (en) * | 2016-11-28 | 2018-07-16 | Общество С Ограниченной Ответственностью "Сенсор Спин Технолоджис" | Gyroscope at n-v centers in diamonds |
WO2018174916A1 (en) * | 2017-03-24 | 2018-09-27 | Lockheed Martin Corporation | Use of waveplates in magnetometer sensor |
RU2684669C1 (en) * | 2017-11-23 | 2019-04-11 | Общество С Ограниченной Ответственностью "Сенсор Спин Технолоджис" | Precision solid-state quantum gyroscope of continuous action on basis of spin ensemble in diamond |
EP4014056A1 (en) | 2019-10-02 | 2022-06-22 | X Development LLC | Magnetometry based on electron spin defects |
DE102019219052A1 (en) | 2019-12-06 | 2021-06-10 | Robert Bosch Gmbh | Method for determining the change in orientation in space of an NMR gyroscope and an NMR gyroscope |
CN112556678B (en) * | 2020-11-24 | 2022-07-19 | 北京航空航天大学 | Method for measuring nuclear polarizability of atomic spin gyroscope based on adiabatic fast channel |
US11940399B2 (en) * | 2021-06-01 | 2024-03-26 | University Of Maryland, College Park | Systems and methods for quantum sensing using solid-state spin ensembles |
CN114719887B (en) | 2022-06-08 | 2022-09-02 | 中国人民解放军国防科技大学 | Online trimming device and method for micro-shell vibrating gyroscope |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20140327439A1 (en) * | 2013-05-01 | 2014-11-06 | Massachusetts Institute Of Technology | Stable three-axis nuclear spin gyroscope |
US20150090033A1 (en) * | 2012-04-13 | 2015-04-02 | The Regents Of The University Of California | Gyroscopes based on nitrogen-vacancy centers in diamond |
US20170343695A1 (en) * | 2016-05-31 | 2017-11-30 | Lockheed Martin Corporation | Magneto-Optical Detecting Apparatus and Methods |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB612832A (en) * | 1946-02-01 | 1948-11-18 | Arthur Tisso Starr | Improvements in or relating to radio echo systems |
US4219775A (en) * | 1969-06-11 | 1980-08-26 | Westinghouse Electric Corp. | Electron spin echo system having magnetic field shift during generation of the echo signal |
US4326803A (en) * | 1979-09-20 | 1982-04-27 | Northrop Corporation | Thin film laser gyro |
US7902530B1 (en) * | 2006-04-06 | 2011-03-08 | Velayudhan Sahadevan | Multiple medical accelerators and a kV-CT incorporated radiation therapy device and semi-automated custom reshapeable blocks for all field synchronous image guided 3-D-conformal-intensity modulated radiation therapy |
US7898356B2 (en) * | 2007-03-20 | 2011-03-01 | Nuvotronics, Llc | Coaxial transmission line microstructures and methods of formation thereof |
WO2009073740A2 (en) | 2007-12-03 | 2009-06-11 | President And Fellows Of Harvard College | Spin based magnetometer |
US9664767B2 (en) * | 2013-05-17 | 2017-05-30 | Massachusetts Institute Of Technology | Time-resolved magnetic sensing with electronic spins in diamond |
-
2013
- 2013-05-01 US US13/874,718 patent/US9417068B2/en active Active
-
2016
- 2016-07-25 US US15/218,401 patent/US20170138735A1/en not_active Abandoned
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150090033A1 (en) * | 2012-04-13 | 2015-04-02 | The Regents Of The University Of California | Gyroscopes based on nitrogen-vacancy centers in diamond |
US9689679B2 (en) * | 2012-04-13 | 2017-06-27 | The Regents Of The University Of California | Gyroscopes based on nitrogen-vacancy centers in diamond |
US20140327439A1 (en) * | 2013-05-01 | 2014-11-06 | Massachusetts Institute Of Technology | Stable three-axis nuclear spin gyroscope |
US9417068B2 (en) * | 2013-05-01 | 2016-08-16 | Massachusetts Institute Of Technology | Stable three-axis nuclear spin gyroscope |
US20170343695A1 (en) * | 2016-05-31 | 2017-11-30 | Lockheed Martin Corporation | Magneto-Optical Detecting Apparatus and Methods |
Cited By (36)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10725124B2 (en) | 2014-03-20 | 2020-07-28 | Lockheed Martin Corporation | DNV magnetic field detector |
US10277208B2 (en) | 2014-04-07 | 2019-04-30 | Lockheed Martin Corporation | Energy efficient controlled magnetic field generator circuit |
US20160146904A1 (en) * | 2014-09-25 | 2016-05-26 | Lockheed Martin Corporation | Micro-dnv device |
US10168393B2 (en) * | 2014-09-25 | 2019-01-01 | Lockheed Martin Corporation | Micro-vacancy center device |
US10466312B2 (en) | 2015-01-23 | 2019-11-05 | Lockheed Martin Corporation | Methods for detecting a magnetic field acting on a magneto-optical detect center having pulsed excitation |
US10241158B2 (en) | 2015-02-04 | 2019-03-26 | Lockheed Martin Corporation | Apparatus and method for estimating absolute axes' orientations for a magnetic detection system |
US10408889B2 (en) | 2015-02-04 | 2019-09-10 | Lockheed Martin Corporation | Apparatus and method for recovery of three dimensional magnetic field from a magnetic detection system |
US10012704B2 (en) | 2015-11-04 | 2018-07-03 | Lockheed Martin Corporation | Magnetic low-pass filter |
US10120039B2 (en) | 2015-11-20 | 2018-11-06 | Lockheed Martin Corporation | Apparatus and method for closed loop processing for a magnetic detection system |
US10333588B2 (en) | 2015-12-01 | 2019-06-25 | Lockheed Martin Corporation | Communication via a magnio |
US10088452B2 (en) | 2016-01-12 | 2018-10-02 | Lockheed Martin Corporation | Method for detecting defects in conductive materials based on differences in magnetic field characteristics measured along the conductive materials |
US10088336B2 (en) | 2016-01-21 | 2018-10-02 | Lockheed Martin Corporation | Diamond nitrogen vacancy sensed ferro-fluid hydrophone |
US10338162B2 (en) | 2016-01-21 | 2019-07-02 | Lockheed Martin Corporation | AC vector magnetic anomaly detection with diamond nitrogen vacancies |
US10006973B2 (en) | 2016-01-21 | 2018-06-26 | Lockheed Martin Corporation | Magnetometer with a light emitting diode |
US10520558B2 (en) | 2016-01-21 | 2019-12-31 | Lockheed Martin Corporation | Diamond nitrogen vacancy sensor with nitrogen-vacancy center diamond located between dual RF sources |
US10677953B2 (en) | 2016-05-31 | 2020-06-09 | Lockheed Martin Corporation | Magneto-optical detecting apparatus and methods |
US10527746B2 (en) | 2016-05-31 | 2020-01-07 | Lockheed Martin Corporation | Array of UAVS with magnetometers |
US10317279B2 (en) | 2016-05-31 | 2019-06-11 | Lockheed Martin Corporation | Optical filtration system for diamond material with nitrogen vacancy centers |
US10571530B2 (en) | 2016-05-31 | 2020-02-25 | Lockheed Martin Corporation | Buoy array of magnetometers |
US10126377B2 (en) | 2016-05-31 | 2018-11-13 | Lockheed Martin Corporation | Magneto-optical defect center magnetometer |
US10345396B2 (en) | 2016-05-31 | 2019-07-09 | Lockheed Martin Corporation | Selected volume continuous illumination magnetometer |
US10338163B2 (en) | 2016-07-11 | 2019-07-02 | Lockheed Martin Corporation | Multi-frequency excitation schemes for high sensitivity magnetometry measurement with drift error compensation |
US10371765B2 (en) | 2016-07-11 | 2019-08-06 | Lockheed Martin Corporation | Geolocation of magnetic sources using vector magnetometer sensors |
US10281550B2 (en) | 2016-11-14 | 2019-05-07 | Lockheed Martin Corporation | Spin relaxometry based molecular sequencing |
US10345395B2 (en) | 2016-12-12 | 2019-07-09 | Lockheed Martin Corporation | Vector magnetometry localization of subsurface liquids |
US10359479B2 (en) | 2017-02-20 | 2019-07-23 | Lockheed Martin Corporation | Efficient thermal drift compensation in DNV vector magnetometry |
US10408890B2 (en) | 2017-03-24 | 2019-09-10 | Lockheed Martin Corporation | Pulsed RF methods for optimization of CW measurements |
US10459041B2 (en) | 2017-03-24 | 2019-10-29 | Lockheed Martin Corporation | Magnetic detection system with highly integrated diamond nitrogen vacancy sensor |
US10379174B2 (en) | 2017-03-24 | 2019-08-13 | Lockheed Martin Corporation | Bias magnet array for magnetometer |
US10338164B2 (en) | 2017-03-24 | 2019-07-02 | Lockheed Martin Corporation | Vacancy center material with highly efficient RF excitation |
US10330744B2 (en) | 2017-03-24 | 2019-06-25 | Lockheed Martin Corporation | Magnetometer with a waveguide |
US10371760B2 (en) | 2017-03-24 | 2019-08-06 | Lockheed Martin Corporation | Standing-wave radio frequency exciter |
US10274550B2 (en) | 2017-03-24 | 2019-04-30 | Lockheed Martin Corporation | High speed sequential cancellation for pulsed mode |
US10228429B2 (en) | 2017-03-24 | 2019-03-12 | Lockheed Martin Corporation | Apparatus and method for resonance magneto-optical defect center material pulsed mode referencing |
CN111077581A (en) * | 2019-05-17 | 2020-04-28 | 吉林大学 | Tunnel water inrush three-dimensional nuclear magnetic resonance advanced detection device and imaging method |
CN110600880A (en) * | 2019-09-19 | 2019-12-20 | 北京航空航天大学 | Circularly polarized frequency-adjustable solid color center microwave control system and method without phase shifter |
Also Published As
Publication number | Publication date |
---|---|
US20140327439A1 (en) | 2014-11-06 |
US9417068B2 (en) | 2016-08-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20170138735A1 (en) | Stable three-axis nuclear spin gyroscope | |
Ajoy et al. | Stable three-axis nuclear-spin gyroscope in diamond | |
US9689679B2 (en) | Gyroscopes based on nitrogen-vacancy centers in diamond | |
Ortu et al. | Simultaneous coherence enhancement of optical and microwave transitions in solid-state electronic spins | |
US8547090B2 (en) | Electronic spin based enhancement of magnetometer sensitivity | |
Obata et al. | Optical ring cavity search for axion dark matter | |
Ledbetter et al. | Gyroscopes based on nitrogen-vacancy centers in diamond | |
US9383208B2 (en) | Electromechanical magnetometer and applications thereof | |
Cochrane et al. | Vectorized magnetometer for space applications using electrical readout of atomic scale defects in silicon carbide | |
Langer et al. | Long-lived qubit memory using atomic ions | |
Hodges et al. | Timekeeping with electron spin states in diamond | |
Stanwix et al. | Coherence of nitrogen-vacancy electronic spin ensembles in diamond | |
Kitching et al. | Atomic sensors–a review | |
Sidles | Folded Stern-Gerlach experiment as a means for detecting nuclear magnetic resonance in individual nuclei | |
Zhang et al. | Inertial rotation measurement with atomic spins: From angular momentum conservation to quantum phase theory | |
Donley | Nuclear magnetic resonance gyroscopes | |
US7915891B2 (en) | MEMS device with tandem flux concentrators and method of modulating flux | |
US10762954B2 (en) | Quantum metrology and quantum memory using defect sates with spin-3/2 or higher half-spin multiplets | |
CN104697512B (en) | A kind of diamond colour center gyroscope and method for measuring angular velocity based on Aharonov Anandan geometry phases | |
RU2661442C2 (en) | Gyroscope at n-v centers in diamonds | |
Gill et al. | A review of MEMS vibrating gyroscopes and their reliability issues in harsh environments | |
Li et al. | Lorentz force magnetometer using a micromechanical oscillator | |
Wang | Precision measurement with atom interferometry | |
Fadeev et al. | Ferromagnetic gyroscopes for tests of fundamental physics | |
Zhao et al. | Inertial measurement with solid-state spins of nitrogen-vacancy center in diamond |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: MASSACHUSETTS INSTITUTE OF TECHNOLOGY, MASSACHUSET Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CAPPELLARO, PAOLA;AJOY, ASHOK;SIGNING DATES FROM 20170427 TO 20170428;REEL/FRAME:042633/0901 |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |