CN108415206A - The light pulse generation method of the arbitrary superposition state of three-lever system quantum bit can be created - Google Patents
The light pulse generation method of the arbitrary superposition state of three-lever system quantum bit can be created Download PDFInfo
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- G—PHYSICS
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- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
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- G02F1/3526—Non-linear optics using two-photon emission or absorption processes
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/29—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the position or the direction of light beams, i.e. deflection
- G02F1/33—Acousto-optical deflection devices
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Abstract
The invention discloses the light pulse generation methods that can create the arbitrary superposition state of three-lever system quantum bit, using the time-dependent Schrodinger equation of the Converse solved three-lever system of invariant theory, structure can generate the field intensity information of one group of double-colored light pulse of the arbitrary superposition state of quantum bit, use Arbitrary Waveform Generator and acousto-optic modulator, generate double-colored light pulse, the extra discretion of bi-coloured light pulsed field persistent erection is used to optimize the shape of pulse, it is allowed to show robustness to frequency detuning present in system, it is sufficiently small to the off-resonance excitation of background ions present in system, to which the arbitrary superposition state of quantum bit is created with fidelity within short action time；The light pulse that the present invention generates can generate the arbitrary superposition state of a quantum bit within the action time of 4 μ s, and the fidelity within the scope of the frequency detuning of ± 340kHz is not less than 99.5%, be no more than 2% to the off-resonance excitation of background ions.
Description
Technical field
The invention belongs to quantum calculation fields, and in particular to can manipulate the arbitrary superposition that quantized system generates quantum bit
The light pulse of state.
Background technology
Quantum calculation be quantum information processing in an important branch, big prime factors decompose, global search and
With the arithmetic speed that traditional counting algorithm is incomparable in the problems such as biomolecule is simulated.Using light pulse in a short time with
It is the first step for opening quantum calculation that quantum bit is initialised to an arbitrary superposition state by high fidelity.But in physical system
It is inevitably present some disturbing factors, such as frequency detuning, distribution of light intensity fluctuation, phase of the field fluctuation, off-resonance excitation
Deng interference.How light pulse is generated, is allowed to that stronger robustness is presented to these interference when manipulating quantum bit, together
When have action time it is short, the high feature of fidelity is one, quantum calculation field urgent problem to be solved.
In the physical system of many carrying quantum calculations, rare earth ion of the random doping in mineral crystal is a kind of ratio
More competitive carrier, because the coherence time of quantum bit can be up to 6 hours, and such crystal is cheap and
Commercialization.Within the system, quantum bit is characterized by one group of assemblage ion on inhomogeneous broadening line, to be entrained in Y2SiO5It is brilliant
Pr in body3+For, their optical transition frequency shows the full width at half maximum (FWHM) of ± 170kHz at 605.977nm.Quantum bit
Two energy levels between coupling implemented by optical transition, constitute a three-lever system.In such three-lever system
In the arbitrary superposition state of a quantum bit is created with high fidelity, light pulse must satisfy following condition, and (1) is to quantum bit
The fidelity of manipulation existing frequency detuning between quantum bit ion is presented stronger robustness, i.e., fidelity ±
Close to ideal value 1 within the scope of 170kHz；(2) in frequency domain with quantum bit ion at a distance of be more than 3.5MHz its
The off-resonance excitation of its ion is sufficiently small, in order to avoid interference quantum bit ion；(3) pulse operating time is as short as possible.
The light pulse of manipulation quantized system is broadly divided into three types at present.The first is simple resonant impulse, such as side
Wave impulse, Gaussian pulse etc., this pulse operating time is short, but more sensitive to disturbing factor present in system.Second
Kind is adiabatic approximation light pulse, it has preferable robustness to disturbing factor present in system, but because is adiabatic mistake
Journey is so pulse operating time is longer.The third is the adiabatic shortcut light pulse based on nonadiabatic process, in certain physical systems
In be proved to can within short action time with high fidelity and strong robustness realize quantum cloth inning transfer.But
The transfer of cloth inning is only a special state in the arbitrary superposition state of quantum bit, arbitrary superposition state be it is essential in quantum manipulation and
A kind of general metamorphosis of the powerful operational capability of quantum computer can fully be developed.At present there are the three-level quantum of frequency detuning
In system, such as rare earth ion system, the light pulse of the arbitrary superposition state of quantum bit is generated still with high fidelity in a short time
It has not been reported.
Invention content
Present invention solves the technical problem that being：Pulse operating time is long, poor robustness；The present invention seek it is a kind of generate one
The method of the double-colored light pulse of group, the double-colored light pulse is equal by two durations, amplitude, frequency and position mutually different pulse group
At the two acts on the three-level quantized system being made of two quantum bit energy levels and an excited level simultaneously, can grasp
The quantized system is controlled from initial state | 1>Generate the arbitrary superposition state of quantum bitWherein θa∈ [0, π],Under certain condition, it is generated
Light pulse has following feature：
A. pulse operating time is short, and under the premise of pulse Rabi frequency is no more than 2MHz, action time is no more than 4 μ s；
B. the fidelity for generating the arbitrary superposition state of quantum bit is not less than 99.5%；
C. there is to frequency detuning present in quantized system within the scope of at least ± 170kHz robustness；
D. the off-resonance of other ions other than quantum bit ion center frequency 3.5MHz excitation is no more than
2%.
In order to achieve the above object, the technical solution adopted by the present invention is as follows：
The light pulse generation method that the arbitrary superposition state of three-lever system quantum bit can be created, in a three-lever system
Light arteries and veins is obtained using the time-dependent Schrodinger equation based on the Converse solved three-lever system of Lewis-Riesenfeld invariant theories
The amplitude and position phase of punching, this amplitude and position, which are mutually inputted Arbitrary Waveform Generator and generated, has amplitude and position phase identical with light pulse
Radio signal obtains+1 grade using the acousto-optic modulator in this radio signal driving continuous laser light path or -1 grade of deviation is defeated
Light extraction generates one group of double-colored light pulse.
The double-colored light pulse of generation is impinged perpendicularly in three-level quantized system medium, double-colored light pulse and quantized system
Medium interaction generates the arbitrary superposition state of quantum bit.Compared with prior art, the present invention has following distinguishing feature：
The double-colored light pulse generated is suitable for three-level quantized system, including two act on still frequency, amplitude simultaneously
The above-mentioned parameter of the light pulse being mutually all different with position, light pulse can completely be controlled by Arbitrary Waveform Generator and acousto-optic modulator
System.
Double-colored light pulse can generate the arbitrary superposition state of a quantum bit, including two quantum in three-lever system
Arbitrary placement's number distribution between bit energy level mutually regulates and controls with arbitrary opposite position.
The starting of double-colored light pulse and stop value can be that zero can also be not zero, and can generate the arbitrary folded of quantum bit
Add state.
The amplitude of double-colored light pulse changes over time, but frequency does not change over time mutually with position.
The duration of light pulse in theory can be arbitrary short, as long as distribution of light intensity is sufficiently large, is for maximum Rabi frequency
The light field of 2MHz, of length no more than 4 μ s of light pulse.
Description of the drawings
Fig. 1 is to be entrained in Y2SiO5Pr in crystal3+Related level structure figure；
Fig. 2 is that light pulse changes over time figure in the Rabi frequency with light pulse in quantized system mechanism；
Fig. 3 is light pulse in the state evolution figure with quantum bit in quantized system mechanism；
Fig. 4 is that light pulse changes over time figure in the Rabi frequency with light pulse in quantized system mechanism；
Fig. 5 is that light pulse changes over time figure in the state with quantum bit in quantized system mechanism；
Fig. 6 is that light pulse is changing over time figure with its Rabi frequency in quantized system mechanism；
Fig. 7 is that light pulse changes over time figure in the state with quantum bit in quantized system mechanism；
Fig. 8 is fidelity and the frequency that light pulse generates target quantum bit superposition state after being acted on quantized system
Dependence graph between mismatching angle；
Fig. 9 be light pulse adjust the distance after being acted on quantized system quantum bit ion be Δ MHz background ions
Off-resonance excite situation map；
Figure 10 is that light pulse is changing over time figure with the Rabi frequency in quantized system mechanism；
Figure 11 is fidelity and the frequency detuning that light pulse generates objective quantum state after being acted on quantized system
Between dependence graph；
Figure 12 be light pulse adjust the distance after being acted on quantized system quantum bit ion be Δ MHz background ions
Off-resonance excite situation map；
Wherein, Ω in figurepIt is energy level | 2>To energy level | e>Optical transition Rabi frequency；ΩsIt is energy level | 0>To energy level | e>
Optical transition Rabi frequency；It is | 0>To energy level | e>Optical transition position phase；T is pulse operating time；PmT moment from
Son exists | the probability of m ＞ states；M=0,1, e；F is the fidelity for generating target state；Δ is anti-resonance frequency mismatching angle.
Specific implementation mode
The invention will be further described with reference to the accompanying drawings and embodiments.
Embodiment one：
The light pulse generation method that the arbitrary superposition state of three-lever system quantum bit can be created, according to the initial state of system | 1>
With target stateWherein θaIn [0, π] range,In [0,2 π] range
Value, using the adiabatic shortcut technology Converse solved three-lever system based on Lewis-Riesenfeld invariant theories when containing
Schrodinger equation obtains the amplitude and position phase of two light pulses, this amplitude is mutually inputted with position Arbitrary Waveform Generator generating amplitude and
Position phase radio signal identical with light pulse, drives the acousto-optic modulator in continuous laser light path to obtain using this radio signal
To+1 grade or -1 grade of deviation output light, one group of double-colored light pulse is generated；
Wherein：The driving frequency of acousto-optic modulator is faom, laser frequency is f in continuous laser light pathlaser, the amount
Sub- bit is by two energy levels | and 0>With | 1>It characterizes, difference on the frequency between them is f0-1, electronics is from energy level | and 1>To energy level | e>'s
Optical transition frequency is νp, electronics is from energy level | 0 ＞ to energy level | e>Optical transition frequency be νs, driving acousto-optic modulator act in
|1>-|e>The frequency of the radio signal of the light pulse of transition is fp, driving acousto-optic modulator act in | 0>-|e>Transition
The frequency of radio signal of light pulse be fs, the two meets fp=faom, fs=faom+f0-1；flaser+fp=νp；Two wireless
The position of electric signal is mutually expressed as：WithAmplitude is expressed as：EpAnd Es；
Then meet：EpAnd EsThe two changes over time, and is determined by following relational expressions：
μ in formulap,sIt is | 1>-|e>With | 0>-|e>The transition dipole moment of optical transition；Ωp,sIt is Lapie's frequency of two light pulses
Rate；C is the Rabi frequency Ω from light pulsep,sTo radio signal amplitude Ep,sConversion coefficient, determined by experimental system；Lapie
Frequency omegap,sIt is shown below dependent on time t：
In formulaWithIt is function β (t) and γ (t) time differentials；Wherein γ (t) is folded by a series of Fourier components
Add：
T in formulafIt is the duration of pulse (unit is the second)；N is positive integer；anThe coefficient of corresponding Fourier components, β (t) according to
Rely and is shown below in γ (t)：
Include 8 degree of freedom (a in the amplitude for the double-colored light pulse that above-mentioned technical proposal generatesn, n=1,2,3 ... 8),
A is adjusted within the scope of real numbernValue, the light pulse of different performance can be generated；anTake the bi-coloured light arteries and veins generated when arbitrary real number value
Punching is only applicable to, there is no the quantized system that frequency detuning and off-resonance excite, quantum ratio can be generated in this quantized system
Special arbitrary superposition state.
Attached drawing 1 is to be entrained in Y2SiO5Pr in crystal3+Related level structure schematic diagram, illustrate this skill for it
The applicable three-lever system of art scheme；Ground state and excitation state separately include three hyperfine energy levels in figure, | e ＞ are an excitations
State, | 0>With | 1>It is two energy levels for characterizing quantum bit, coupling between the two passes through | 1>| e ＞ and | 1>| e ＞ two
Optical transition is implemented.
With target state in embodimentFor, i.e. θa=π/4,To illustrate
The shape and its working performance of light pulse.Aforementioned double-colored light pulse is substituted into the coupling of description light and the effect of three-level quantized system
In the differential equation, the working performance of light pulse is simulated in Matlab.Generate the fidelity F definition of quantum bit target state such as
Under：
F=|<ψtarget|ψ(tf)>|2
Wherein | ψ (tf)>It is to solve for the quantum state that three-level coupled differential obtains | ψ (t)>In t=tfThe state letter at moment
Number.
At the end of light pulse and quantized system act on, light pulse excites the off-resonance of background ions and uses | ψ (tf)〉
| 1>State, | 0 ＞ states and | e>The probability P of statemIt characterizes, expression formula is：
Pm=| ＜ m | ψ (tf)>|2
Wherein m=0,1, e.
Embodiment two：
The light pulse generation method for creating the arbitrary superposition state of three-lever system quantum bit on the basis of embodiment one, formula
(4) all a innValue is zero.At this time：
Based on β (t) shown in this γ (t) and (5) formula, the Rabi frequency of the light pulse generated by formula (2) and (3) is referring to attached drawing
2, wherein solid line is Ωp, dotted line is Ωs, pulse operating time is 4 μ s, and the starting of Rabi frequency and stop value are not equal to zero,
Maximum instantaneous Rabi frequency is no more than 0.5MHz.
Attached drawing 3 be pulse with without in detuning quantized system mechanism, quantum state | ψ (t)>Evolution condition at any time.
Initial time, quantum state are in | and 1>State；In end-of-pulsing, i.e., t=4 μ s, quantum state exist | and 0>With | 1>Probability be
50%, this and target stateIt matches.
Light pulse generates objective quantum state in this embodiment | ψtargetThe fidelity F=1 of ＞, but this double-colored light pulse is only
Suitable for there is no the quantized systems of frequency detuning and off-resonance excitation.
The advantages of light pulse generated in the present embodiment is that the absolute value of required instantaneous Rabi frequency is no more than 0.5MHz,
The quantized system being limited for distribution of light intensity is an advantage；The disadvantage is that Rabi frequency is not in initial and end time value
Zero, this requires the response speeds of the acousto-optic modulator in system to want sufficiently fast, and near quantum bit centre frequency not
In the presence of the background ions or atom etc. that may be excited.
Embodiment three：
The light pulse generation method for creating the arbitrary superposition state of three-lever system quantum bit on the basis of embodiment one, formula
(4) a innAll even items and odd term meet following two conditions respectively：
a1+3a3+5a5+7a7=0,
a2+2a4+3a6+4a8=-0.5.
So two light pulses are zero in initial and end time Rabi frequency, i.e. Ωp,s(t=0, tf)=0.By appointing
Meaning meets a of the two relational expressionsnValue substitutes into (4) formula, and the controllable quantized system of light pulse of structure creates target state | ψtarget
>, this sentences simplest situation a2=-0.5, a1.3.4.5.6.7.8For=0, illustrate the shape and its working performance of light pulse.
Attached drawing 4 is the Rabi frequency of double-colored light pulse in this embodiment, is zero in initial and end time value, keeps away
Multiple Fourier frequency components that the field strength change dramatically at endpoint is brought in a frequency domain are exempted from there are the quantum of background ions
On being influenced caused by quantum bit possibility in system.
Attached drawing 5 is that double-colored light pulse is with without in detuning quantized system mechanism in this embodiment, and quantum state is at any time
Evolution condition.The initial state of system is | 1>, terminate state and be located at | 0>With | 1>Probability be 50%.
Light pulse generates objective quantum state in this embodiment | ψtarget>Fidelity F=1, but the double-colored light pulse is only
Suitable for there is no the quantized systems of frequency detuning and off-resonance excitation.
The advantages of light pulse generated in the present embodiment is that the absolute value of required instantaneous Rabi frequency increases compared with embodiment two
Greatly, but still less than 1MHz, the quantized system being limited for distribution of light intensity is an advantage；Rabi frequency is in initial and termination
The value at quarter is zero, and is changed over time slowly, this point reduces the requirement to the response time of acousto-optic modulator；Make in pulse
The about 1.2 μ s of time of excitation state are in process intermediate ion, and the coherence time of Pr ions is up to 150 μ s, effectively reduces and moves back
Relevant possibility.
Example IV：
The light pulse generation method for creating the arbitrary superposition state of three-lever system quantum bit on the basis of embodiment one is led to
Over-scan anValue, light pulse and quantized system effect end time, detection generate target state fidelity and to background
The off-resonance excitation of ion obtains a in formula (4) with the variation relation of frequency detuningnOptimal value.Such as：a1.3.5.7=0,
a2=-1.10, a4=0.09, a6=0.06 and a8=0.06, the Rabi frequency of the light pulse based on the generation of these parameters is shown in
Shown in attached drawing 6.Pulse operating time is still 4 μ s, and Rabi frequency is increased compared with embodiment one and example two, but maximum Lapie's frequency
Rate is still less than 1.5MHz.
Attached drawing 7 is the light pulse that is generated in the present embodiment with without in detuning quantized system mechanism, and quantum state is at any time
Between evolution condition.Quantum state is carved at the beginning to be in | 1>State, in end-of-pulsing t=4 μ s, quantum state is in | and 0>With | 1>
Probability be 50%.
Attached drawing 8 is the light pulse that is generated in the present embodiment to carry out interaction and terminates with there are the quantized system of frequency detuning
When, generate objective quantum state | ψtarget>Fidelity F with the variation relation figure of frequency detuning Δ, wherein Δ is in light pulse
Frequency of heart and quantum bit ion or the difference of background ions coformational transition frequency, i.e. anti-resonance frequency mismatching angle.In no frequency
When rate is detuning, i.e., Δ=0, fidelity are 1；Near centre frequency within the scope of ± 340kHz, fidelity F>99.5%, it shows
Stronger robustness；For rare earth ion system shown in Fig. 1, the robustness within the scope of ± 340kHz is enough, because
The full width at half maximum (FWHM) of quantum bit absorption peak is 170kHz；In addition, behavior of the fidelity between ± 340kHz to 3.5MHz is unrelated
It is critical, because quantum bit ion is located in the frequency window of a zero absorption, the centre frequency frequency of distance window of bit ion
The boundary about 3.5MHz of mouth.It is more than the background ions of 3.5MHz for mismatching angle, the value of fidelity is nonsensical to quantum calculation,
Its behavior is not considered.
Attached drawing 9 is light pulse at the end of with quantized system mechanism, and quantum bit ion of adjusting the distance is the back of the body of Δ MHz
The off-resonance of scape ion excites situation, is presented as the distributive law P in three energy states in pulse termination moment ionm.For Fig. 1
For shown rare earth ion system, it is of interest that the off-resonance other than 3.5MHz excites situation.Ideally light pulse is right |
Δ | the ion of >=3.5MHz does not have any excitation, i.e., does not touch their state, still in initial state | and 1>State.Δ=±
When 3.5MHz, about 1.9% probability ion is from initial state | and 1>It is transferred to | 0>State is located at | e>Probability in state is zero.It considers
Background ions density at this frequency detuning is only the 1/6 of quantum bit ion concentration, therefore 1.9% transfer probability foot
Enough small, being interfered caused by quantum bit ion can ignore.
The advantages of light pulse generated in the present embodiment is the fidelity that pulse is manipulated with quantum bit state, to swashing
Stronger robustness is presented in existing frequency detuning between light frequency and quantum bit ion, is nearby deposited to quantum bit ion
Off-resonance excitation it is sufficiently small, this point be there are frequency detuning and off-resonance excitation quantized system in carry out quantum calculation
Key element；The time that excitation state is in impulse action intermediate ion further decreases, about 0.63 μ s, further drops
The low probability of decoherence.
Embodiment five
Based on example IV, target state is generated from the initial arbitrary superposition state of quantum bit in three-lever system | 1>State
Light pulse method, do following variation：
t→tf-t,Ωp,s→-Ωp,s
Will two light fields amplitude at any time be in Back Up, while position mutually increase 180 degree, it is other to remain unchanged,
One group of new double-colored light pulse is generated, this light pulse is applied in quantized system, may be implemented from arbitrarily quantum bit superposition stateCreate | ψtarget>=| 1>State.This is sentencedFor say
The working performance of Mingguang City's pulse.
Attached drawing 10 is that the Rabi frequency of light pulse in this embodiment changes with time relational graph, and Rabi frequency is at any time
The presentation time reversal relationship of variation and the situation in attached drawing 6.
Attached drawing 11 is light pulse and when being interacted there are the quantized system of frequency detuning in this embodiment, from quantum
Bit initial stateWherein | Δ |≤3.5MHz and background ions initial state | ψin>=| 1>,
In | Δ |>3.5MHz generates objective quantum state | and 1>Fidelity F with frequency detuning Δ variation relation.It is lost in no frequency
When humorous, i.e., Δ=0, fidelity are 1；Near centre frequency within the scope of ± 340kHz, F>99%, show preferable robust
Property.Spline smoothing of the fidelity at 3.5MHz is as caused by the different original state in both sides, because for amount shown in FIG. 1
For subsystem, during quantum calculation, | Δ | the original state of the ion of >=3.5MHz is always | 1>State, only quantum
The original state of bit can be because of situation.
Attached drawing 12 is light pulse in this embodiment at the end of with quantized system mechanism, adjust the distance quantum bit from
Son is that the off-resonance of the background ions of Δ MHz excites situation map, and in Δ=± 3.5MHz, about 0.3% ion deflection is just
The superposition state of beginning, | e>Probability in state is zero.0.3% deviation is interfered caused by quantum bit ion to be ignored.
The advantages of light pulse generated in the present embodiment same example IV, the amount being a difference in that in the present embodiment of the two
Sub- manipulation process is generated from an arbitrary superposition state | 1>State.
The double-colored light pulse that above-mentioned technical proposal generates can be used for being made quantum computer or quantum based on rare earth ion
The component part of memory, the two devices includes：The quantized system of doping with rare-earth ions provides low temperature environment to quantized system
To keep the 2K cryostats of its long coherence time, the laser of continuous laser output, previously described light pulse to generate system
System, including Arbitrary Waveform Generator, acousto-optic modulator and some common optical component such as speculums, lens, wave plate, polarization
Piece etc..It is worth noting that although the technical program is developed for three-lever system, under given conditions, three energy
Grade system can collapse for a two-level energy system, to which structure can be laid out two-level energy system number transfer and create folded
Add the light pulse of state.These technical minor changes or modification still fall within the scope that the present invention covers.
The technical program unspecified part belongs to technology well known to those skilled in the art.
Claims (9)
1. the light pulse generation method of the arbitrary superposition state of three-lever system quantum bit can be created, adopted in a three-lever system
Two light are obtained with the time-dependent Schrodinger equation based on the Converse solved three-lever system of Lewis-Riesenfeld invariant theories
This amplitude and position are mutually inputted Arbitrary Waveform Generator generating amplitude and position phase nothing identical with light pulse by the amplitude and position phase of pulse
Line electric signal drives the acousto-optic modulator in continuous laser light path to obtain+1 grade or -1 grade of deviation output using this radio signal
Light generates one group of double-colored light pulse.
2. the light pulse generation method according to claim 1 for creating the arbitrary superposition state of three-lever system quantum bit,
The double-colored light pulse of generation is impinged perpendicularly in three-level quantized system medium, double-colored light pulse and quantized system medium are mutual
Effect generates the arbitrary superposition state of quantum bit.
3. the light pulse generation method according to claim 1 for creating the arbitrary superposition state of three-lever system quantum bit,
According to the initial state of system | 1>With target stateWherein θaIn [0, π] range,The value in [0,2 π] range, it is Converse solved using the adiabatic shortcut technology based on Lewis-Riesenfeld invariant theories
The time-dependent Schrodinger equation of three-lever system；
Wherein：The driving frequency of acousto-optic modulator is faom, laser frequency is f in continuous laser light pathlaser, the quantum ratio
Spy is by two energy levels | and 0>With | 1>It characterizes, difference on the frequency between them is f0-1, electronics is from energy level | and 1>To energy level | e>Light jump
It is ν to move frequencyp, electronics is from energy level | and 0>To energy level | e>Optical transition frequency be νs, driving acousto-optic modulator act in | 1>-
|e>The frequency of the radio signal of the light pulse of transition is fp, driving acousto-optic modulator act in | 0>-|e>The light of transition
The frequency of the radio signal of pulse is fs, the two meets fp=faom, fs=faom+f0-1；flaser+fp=νp；Two aerograms
Number position be mutually expressed as：WithAmplitude amplitude is expressed as：EpAnd Es；
Then meet：EpAnd EsThe two changes over time, and is determined by following relational expressions：
μ in formulap,sIt is | 1>-|e>With | 0>-|e>The transition dipole moment of optical transition；Ωp,sIt is the Rabi frequency of two light pulses；C
It is the Rabi frequency Ω from light pulsep,sTo radio signal amplitude Ep,sConversion coefficient, determined by experimental system；Rabi frequency
Ωp,sIt is shown below dependent on time t：
In formulaWithIt is function β (t) and γ (t) time differentials；Wherein γ (t) be superimposed by a series of Fourier components and
At：
T in formulafIt is the duration of pulse (unit is the second)；N is positive integer；anIt is the coefficient of corresponding Fourier components, β (t) is depended on
γ (t) is shown below：
4. the light pulse generation method according to claim 3 for creating the arbitrary superposition state of three-lever system quantum bit,
All a in formula (4)nValue is zero.
5. the light pulse generation method according to claim 3 for creating the arbitrary superposition state of three-lever system quantum bit,
A in formula (4)nAll even items and odd term meet the following conditions respectively：
a1+3a3+5a5+7a7=0,
a2+2a4+3a6+4a8=-0.5.
6. the light pulse generation method according to claim 3 for creating the arbitrary superposition state of three-lever system quantum bit,
By scanning anValue, light pulse and quantized system effect end time, detection generate target state fidelity and to the back of the body
The off-resonance excitation of scape ion obtains a in formula (4) with the variation relation of frequency detuningnOptimal value.
7. the light pulse generation method according to claim 6 for creating the arbitrary superposition state of three-lever system quantum bit,
a1.3.5.7=0, a2=-1.10, a4=0.09, a6=0.06 and a8=0.06.
8. generating target state from the arbitrary superposition state of initial quantum bit | 1>The light pulse method of state, done in three-lever system as
Lower variation：t→tf- t, Ωp,s→-Ωp,s, it is in Back Up at any time by the amplitude of two light fields, while position mutually increases by 180
Degree.
9. generating rare earth ion quantum device made of light pulse according to one of claim 1-8 the methods.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109581589A (en) * | 2019-01-22 | 2019-04-05 | 安徽工业大学 | A kind of single photon polarization method |
| CN110120799A (en) * | 2019-04-17 | 2019-08-13 | 上海大学 | A kind of insulation shortcut method of high-fidelity population inversion in two-level energy system |
| CN112232514A (en) * | 2020-11-06 | 2021-01-15 | 苏州大学 | Optical pulse design method for carrying out high-fidelity control on ensemble qubits |
| CN112418429A (en) * | 2019-08-23 | 2021-02-26 | 中国科学技术大学 | Method and system for realizing CZ door |
| CN114528999A (en) * | 2022-01-21 | 2022-05-24 | 苏州大学 | Optical pulse generation method for carrying out high-fidelity control on ensemble qubits |
| CN114580646A (en) * | 2022-03-16 | 2022-06-03 | 苏州大学 | Method for constructing any geometric quantum logic gate of imperfect system |
| WO2023005949A1 (en) * | 2021-07-28 | 2023-02-02 | 合肥本源量子计算科技有限责任公司 | Quantum bit control signal optimization method and apparatus, and quantum computer |
| CN116011578A (en) * | 2022-12-02 | 2023-04-25 | 浙江大学 | Universal frequency modulation method applied to quantum bit system |
| US11748648B2 (en) | 2019-07-01 | 2023-09-05 | International Business Machines Corporation | Quantum pulse optimization using machine learning |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5768297A (en) * | 1995-10-26 | 1998-06-16 | Lucent Technologies Inc. | Method for reducing decoherence in quantum computer memory |
| JP2001358712A (en) * | 2000-06-12 | 2001-12-26 | Canon Inc | Enciphering device and method |
| JP2005267104A (en) * | 2004-03-17 | 2005-09-29 | Canon Inc | Quantum computing device and method and computing time evaluating method |
| CN101118608A (en) * | 2007-08-23 | 2008-02-06 | 清华大学 | Decompose method for arbitrarily quantum bit gate |
| JP2009031377A (en) * | 2007-07-25 | 2009-02-12 | Nec Electronics Corp | Audio data processor, bit width conversion method and bit width conversion device |
| CN105580363A (en) * | 2013-02-11 | 2016-05-11 | 刘世昌 | Method for implementing quantum computer, quantum communication, and bare-eye 4d holographic television system |
-
2018
- 2018-03-21 CN CN201810234933.5A patent/CN108415206B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5768297A (en) * | 1995-10-26 | 1998-06-16 | Lucent Technologies Inc. | Method for reducing decoherence in quantum computer memory |
| JP2001358712A (en) * | 2000-06-12 | 2001-12-26 | Canon Inc | Enciphering device and method |
| JP2005267104A (en) * | 2004-03-17 | 2005-09-29 | Canon Inc | Quantum computing device and method and computing time evaluating method |
| JP2009031377A (en) * | 2007-07-25 | 2009-02-12 | Nec Electronics Corp | Audio data processor, bit width conversion method and bit width conversion device |
| CN101118608A (en) * | 2007-08-23 | 2008-02-06 | 清华大学 | Decompose method for arbitrarily quantum bit gate |
| CN105580363A (en) * | 2013-02-11 | 2016-05-11 | 刘世昌 | Method for implementing quantum computer, quantum communication, and bare-eye 4d holographic television system |
Non-Patent Citations (3)
| Title |
|---|
| M. B. KENMOE AND L. C. FAI: "Periodically driven three-level systems", 《PHYSICAL REVIEW B 》 * |
| TONG LIU等: "Efficient transfer of an arbitrary qutrit state in circuit quantum electrodynamics", 《OPTICS LETTERS》 * |
| 张信华等: "利用 V 型三能级原子与相干态腔场的拉曼相互作用来传送 N-qubit 的未知原子态", 《苏州科技学院学报》 * |
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| WO2023005949A1 (en) * | 2021-07-28 | 2023-02-02 | 合肥本源量子计算科技有限责任公司 | Quantum bit control signal optimization method and apparatus, and quantum computer |
| US11989624B1 (en) | 2021-07-28 | 2024-05-21 | Origin Quantum Computing Technology (Hefei) Co., Ltd. | Method and apparatus for optimizing a qubit control signal, and quantum computer |
| CN114528999A (en) * | 2022-01-21 | 2022-05-24 | 苏州大学 | Optical pulse generation method for carrying out high-fidelity control on ensemble qubits |
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