CN207010681U - The coaxial free space quantum communications code device in four tunnels - Google Patents
The coaxial free space quantum communications code device in four tunnels Download PDFInfo
- Publication number
- CN207010681U CN207010681U CN201720603913.1U CN201720603913U CN207010681U CN 207010681 U CN207010681 U CN 207010681U CN 201720603913 U CN201720603913 U CN 201720603913U CN 207010681 U CN207010681 U CN 207010681U
- Authority
- CN
- China
- Prior art keywords
- polarization
- light
- optical fibre
- maintaining optical
- wave plate
- 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.)
- Withdrawn - After Issue
Links
Landscapes
- Optical Communication System (AREA)
Abstract
This patent discloses a kind of coaxial free space quantum communications code device in four tunnel, the device is launched 4 tunnel encoded signals coupled to 1 single-mode fiber to ensure that the high accuracy of 4 road quantum light is coaxial, possesses the polarization characteristic of unitary change using single-mode fiber simultaneously, the polarization variations introduced using the scheme of 1/4,1/4,1/2 wave plate combined to optical fiber are compensated to ensure the polarization state of emergent light, and polarization compensation are monitored using BB84 decoder modules to ensure polarization compensation effect.The patent possesses the characteristic of high-axiality and high stability, and confidentiality is higher；The patent has been adapted in Space Quantum Communication to coding module miniaturization, high polarization-maintaining, highly reliable active demand.
Description
Technical field
This patent discloses a kind of free space quantum communications code device of high-axiality, especially suitable for based on polarization
In the quantum communication systems used for free space of coding, the free-space optical communication system based on polarization encoder is applied also for.
Background technology
Secret communication is a kind of transmission mode for allowing communicating pair to exchange information under top-secret state, and many countries are all very
Pay attention to the research of secret communication.The research of Technique on Quantum Communication is linked closely the great needs of problems of national security, it is expected to is increased substantially
Security, information transfer channel capacity and efficiency of information transfer etc., it is the grand strategy direction of future information technology development,
And very likely cause the revolution in many Science and Technology fields, on economic and society progressive generation influence difficult to the appraisal.
Important developed country in the world, the particularly U.S., European Union and Japan have put into a large amount of manpower and materials and have been directed to free space
The theory and experimental study of quantum communications.
In recent years, quantum communications progress is rapid, and remote quantum communications then become the focus of international keen competition.
The technological means of quantum communications at present mainly includes：Quantum Teleportation based on optical-fibre channel, based on free space passage.But due to
The limitation of fiber optic materials, the loss of optical fiber and decoherence can not avoid, and the performance of low loss fiber has approached reason at present
By the limit, become extremely difficult establishing quantum channel at a distance of 2 points of more than 100 kilometers using optical fiber.Free space quantum is believed
Road is one of scheme the most feasible for currently realizing remote quantum communications experiment, and remote free space quantum communications are
Become the focus of international research, free space QKD key coding mode typically uses BB84 schemes, and its key is using single
The polarization state of photon carries out binary coding, and horizontal (H) or+45 ° of (+) linear polarizations correspond to classical bit 0 defined in it；
(V) or -45 ° of (-) linear polarizations correspond to classical bit 1 vertically, and in order to prevent the incoherent attack of listener-in, general use is based on
Quantum key distribution (QKD) technology of state is inveigled to judge whether listener-in, the Main Basiss for judging listener-in are to pass through
Inveigle the proportionate relationship between state and signal state, and the judgement of the receiving efficiency relation pair ratio between 4 kinds of polarization states is to closing
Important, the definitely coaxial quantum coding module of design is to significant with the presence or absence of listener-in.
This patent is directed to the application demand of above free space quantum communications, discloses a kind of definitely coaxial free space amount
Sub- communication code device and its design method, the patent possess the characteristic of high-axiality and high stability, and confidentiality is higher；Simultaneously
Adapt in free space quantum communications to coding module miniaturization, high polarization-maintaining, highly reliable active demand.
The content of the invention
The purpose of this patent is to provide a kind of free space quantum communications code device of high-axiality, and the Patent equipment is special
Not suitable for the quantum communication systems used for free space based on polarization encoder, the free space optical based on polarization encoder is applied also for
Communication system.The patent mainly using same root fibre optical transmission come the coaxial of guaranteed discharge sub-light, so as to obtain a kind of high alignment,
The device of high security.The characteristics of patent, is mainly reflected in：Quantum light launches axiality and stability is high, strong security；.
Patent device is as shown in Figure 1：The Patent equipment is by BB84 polarization encoders module 1, light beam coupling device 2,
One rotatable quarter wave plate 3, the second rotatable quarter wave plate 4, rotatable 1/2 wave plate 5, beam expanding lens 6, that polarization-maintaining cuts light microscopic 7, BB84 is inclined
The decoder module 8 that shakes forms.Wherein BB84 polarization encoders module 1 can be respectively by the first polarization maintaining optical fibre 1-1-1 with LD, with LD's
Second polarization maintaining optical fibre 1-1-2, the 3rd polarization maintaining optical fibre 1-2-1 with LD and the 4th polarization maintaining optical fibre 1-2-2 with LD introduce 4 road quantum
Signal, most of light quantity subsignal in the quantum signal of 4 road after BB84 polarization encoders module 1 respectively with 0 °, 90 ° ,+
45 ° coaxially export with -45 ° of 4 kinds of line polarisations, and 4 kinds of line polarisations collimate output, collimated light difference after light beam coupling device 2 again
Launch after the first rotatable quarter wave plate 3, the second rotatable quarter wave plate 4, rotatable 1/2 wave plate 5, beam expanding lens 6, wherein
Beam expanding lens 6 is used to compress the emergent light angle of divergence, while expands emergent light spot size.
Fraction light in the quantum signal of 4 road is cut after light microscopic 7 reflects by polarization-maintaining enters BB84 decoder modules 8,
BB84 decoder modules 8 can measure simultaneously to the line deviatoric component of 0 °, 90 ° ,+45 ° and -45 ° of incident light, and then monitor outgoing
Light polarization state, by the measurement to being emitted light polarization state, state of polarization auto compensation is carried out using wave plate group to ensure emergent light
Polarization state.The first polarization maintaining optical fibre 1-1-1 with LD, the second polarization maintaining optical fibre 1-1-2 with LD, the 3rd polarization-maintaining light with LD simultaneously
Fine 1-2-1 and the introduced big I of quantum signal energy of the 4th polarization maintaining optical fibre 1-2-2 with LD are received by BB84 decoder modules 8
To signal fed back, it is by energy back information that the energy adjustment of 4 road emergent lights is consistent.
Described BB84 polarization encoders module 1 is by the first polarization maintaining optical fibre 1-1-1 with LD, the second polarization maintaining optical fibre 1- with LD
1-2, the 3rd polarization maintaining optical fibre 1-2-1 with LD and the 4th polarization maintaining optical fibre 1-2-2 with LD, the first wollaston prism 1-1, second
Wollaston prism 1-2, depolarization BS1-3, collimation lens 1-4 and PIN pipe 1-5 compositions.First wollaston prism 1-1 is by band
The two beam crossed polarized lights that LD the first polarization maintaining optical fibre 1-1-1, the second polarization maintaining optical fibre 1-1-2 with LD are exported carry out conjunction beam；Institute
The the second wollaston prism 1-2 stated exports the 3rd polarization maintaining optical fibre 1-2-1 with LD, the 4th polarization maintaining optical fibre 1-2-2 with LD
Two beam crossed polarized lights carry out conjunction beam；Simultaneously beam is closed by the first wollaston prism 1-1, the second wollaston prism 1-2
2 kinds of crossed polarized lights carry out conjunction beam by depolarization BS1-3, ensured by rotating 1-145 ° of transmission end wollaston prism
45 ° of polarization direction deviation between transmitted light and reflected light, ensure 4 road polarised lights respectively with 0 °, 90 ° ,+45 ° and -45 ° line folk prescription
To outgoing, so as to ensure 4 kinds of polarization states coding outputs, collimated light beam is finally sent after collimation lens 1-4, and PIN pipes 1-5
For detecting four tunnel luminous powers.
Described light beam coupling device 2 is made up of coupled lens 2-1, single-mode fiber 2-2 and collimation diversing lens 2-3.
The directional light that BB84 polarization encoders module 1 exports, is coupled in single-mode fiber 2-2, then pass through after first passing around coupled lens 2-1
Cross collimation diversing lens 2-3 collimation outputs.
Described BB84 polarizes decoder module 8 by the first multimode fibre 8-1-1 with detector, more than second with detector
Mode fiber 8-1-2, the 3rd multimode fibre 8-2-1 with detector and the 4th multimode fibre 8-2-2 with detector, the 3rd wet drawing
Depolarization BS 8-3, convergent lens 8-4 composition in this prism 8-1, the 4th wollaston prism 8-2, polarization decoder module.
Part outgoing beam is cut after light microscopic 7 reflects by polarization-maintaining to be entered in BB84 decoder modules 8, first passes around convergent lens 8-4 convergences,
Converging light is divided into transmission and reflection two-way by the depolarization BS 8-3 in polarization decoder module, and transmitted light passes through the 3rd wet Lars
The first multimode fibre 8-1-1 with detector, the second multimode light with detector are introduced separately to after prism 8-1 polarization spectros
Detected in fine 8-1-2, reflected light is introduced separately to detector after the 4th wollaston prism 8-2 polarization spectros
Detected in 3rd multimode fibre 8-2-1, the 4th multimode fibre 8-2-2 with detector；Simultaneously by rotating transmission end the
Three 8-145 ° of wollaston prisms ensure 45 ° of polarization direction deviation between transmitted light and reflected light, so as to ensureing 4 road polarised lights
Respectively with 0 °, 90 ° ,+45 ° and -45 ° line folk prescription to carry out polarized component measurement.The major function of the module is to be used to each road measure
Sub-light energy coincidence and outgoing light polarization state test.
Because 4 road quantum light are exported by same collimating lens 1-4, polarization variations can be introduced, the polarization variations are unitary
Conversion, can be compensated by the first rotatable quarter wave plate 3, the second rotatable quarter wave plate 4, rotatable 1/2 wave plate 5, and
The calculating of wave plate angle is and guided come tests polarization variable quantity by BB84 polarization decoder modules 8, finally compensation effect is carried out
Checking, specific polarization compensation principle refer to documents below:
Wang Shao-Kai.et al.“Realization of Arbitrary Inverse Unitary
Transformation of Single Mode Fibre by Using Three Wave Plates.”
Chin.Phys.Lett.24(9),2471-2474(2007)
In summary, this patent is directed to the application demand of above free space quantum communications, discloses a kind of definitely coaxial
Free space quantum communications code device and its design method, the patent have advantages below：
1st, exit dose sub-light high-axiality：Coupled using the collimated light beam for sending 4 kinds of polarised lights after collimation lens
Outgoing in single-mode fiber is converged to after to another collimation lens by collimation lens to launch, and ensure that the same of 4 road quantum light
Axle is high, and stability is good；
2nd, quantum light energy can monitor：There is optical axis deviation in 4 road quantum light in BB84 polarization encoders module 1, and system is come
Say and be only embodied in energy variation, decoder module 8 can be polarized by BB84 and carry out energy monitoring, while pass through energy measuring
To adjusting four paths energy coincidences, it is ensured that security.
Brief description of the drawings
Fig. 1 is definitely coaxial quantum communications code device schematic diagram.
Fig. 2 is BB84 polarization encoder module diagrams.
Fig. 3 is that BB84 polarizes decoder module schematic diagram.
Embodiment
This patent uses following main devices：
1st, BB84 polarization encoders module 1：The first polarization maintaining optical fibre 1-1-1 with LD, the second polarization maintaining optical fibre 1-1-2 with LD,
The 3rd polarization maintaining optical fibre 1-2-1 with LD and the 4th polarization maintaining optical fibre 1-2-2 with LD uses LP852-SF30, optical fiber core diameter 5.3um；
First wollaston prism 1-1, the second wollaston prism 1-2 select calcite material, and its extinction ratio is better than 100000：1；Disappear
The device that BS1-3 uses Thorlabs companies model BS008 is polarized, it uses wave-length coverage 770-1100nm, and bore is
5mm；Collimation lens 1-4 uses the device of Thorlabs companies model 352150, and focal length 2mm, PIN pipe 1-5 is used
The device of Thorlabs companies model 1110576, uses wave-length coverage 600-1100nm.Component is integrated can be by Shenzhen Guang Yue sections
Skill is integrated；
2nd, light beam coupling device 2：Coupled lens 2-1 collimations diversing lens 2-3 uses Thorlabs companies model
F220FC-B device, system focal length 10.99mm, optical fiber can be directly connected to；, single-mode fiber 2-2 use general single mode light
Fibre, optical fiber core diameter 5.3um；
3rd, rotatable quarter wave plate 3, rotatable quarter wave plate 4：Using the achromatism quarter wave plate of Thorlabs companies, model
For AHWP05M-980, its Specifeca tion speeification：Service band is 700-1200nm；Phase delay degree of accuracy λ/40- λ/230；Rotation
Turn the device that device uses Thorlabs companies model RSP1X15, wave plate is installed in circulator；
4th, rotatable 1/2 wave plate 5：Using the Thorlabs wave plate of achromatism 1/2, model AQWP05M-980, its is main
Performance parameter：Service band is 700-1200nm；Phase delay degree of accuracy λ/40- λ/230；Circulator uses Thorlabs companies
Model RSP1X15 device, wave plate are installed in circulator；
5th, beam expanding lens 6：Conventional beam expanding lens, expand multiple and take 5 times, operating wavelength range 600-1000nm；
6th, polarization-maintaining cuts light microscopic 7：Conventional reflector, it is 5mm to cut light microscopic bore, cuts angular as 22.5 ° ,+(45 °) and-(-
45 °) line polarisation through cutting light microscopic reflection after extinction ratio be better than 5000：1
7th, BB84 polarizes decoder module 8：The first multimode fibre 8-1-1 with detector, the second multimode light with detector
Fine 8-1-2, the 3rd multimode fibre 8-2-1 with detector and the 4th multimode fibre 8-2-2 with detector use Thorlabs
Company model SPCM50A single photon counting module, using conventional multi-mode fiber, use wave-length coverage 400-2400nm, core
Footpath 105um, numerical aperture 0.22；3rd wollaston prism 8-1, the 4th wollaston prism 8-2 select calcite material,
Its extinction ratio is better than 100000：1；Depolarization BS 8-3 use Thorlabs companies model BS008 device, and it uses wavelength
Scope 770-1100nm, bore 5mm；Collimation lens 8-4 uses the device of Thorlabs companies model 352150, and focal length is
2mm；Component is integrated to be integrated by Shenzhen light is more scientific and technological.
As indicated with 1, its working method is as described below for this patent module diagram：
The Patent equipment can by BB84 polarization encoders module 1, light beam coupling device 2, the first rotatable quarter wave plate 3, second
Rotation quarter wave plate 4, rotatable 1/2 wave plate 5, beam expanding lens 6, polarization-maintaining cut light microscopic 7, BB84 polarization decoder modules 8 form.Wherein
BB84 polarization encoders module 1 can pass through the first polarization maintaining optical fibre 1-1-1 with LD, the second polarization maintaining optical fibre 1-1-2, band with LD respectively
LD the 3rd polarization maintaining optical fibre 1-2-1 and the 4th polarization maintaining optical fibre 1-2-2 introducing quantum signals with LD, quantum signal are inclined by BB84
Shake and coaxially exported with 0 °, 90 ° ,+45 ° and -45 ° 4 kinds of line polarisations respectively after coding module 1,4 kinds of line polarisations pass through light beam coupling again
Output is collimated after device 2, collimated light is respectively by the first rotatable quarter wave plate 3, the second rotatable quarter wave plate 4, rotatable 1/2
Launch after wave plate 5, beam expanding lens 6, wherein beam expanding lens 6 is used to compress the emergent light angle of divergence, while expands emergent light spot size, communicates
Light beam is launched to receiving terminal along main optical path, and segment beam is cut after light microscopic 7 reflects by polarization-maintaining enters BB84 decoder modules 8, BB84
Decoder module 8 can measure simultaneously to 0 °, 90 ° ,+45 ° of incident light and -45 ° of polarized components, and then monitor outgoing light polarization
State, by the measurement to being emitted light polarization state, and utilize bibliography " Wang Shao-Kai.et al.
《Realization of Arbitrary Inverse Unitary Transformation of Single Mode Fibre
by Using Three Wave Plates.》Polarization compensation in Chin.Phys.Lett.24 (9), 2471-2474 (2007) "
The angle of principle control wave plate group carrys out the degeneration of compensating polarizing state, so as to ensure the linear polarization state of emergent light.Polarization state is adjusted
After the completion of, fed back by the signal received by BB84 decoder modules 8, adjust the first polarization maintaining optical fibre 1-1- with LD respectively
1st, the second polarization maintaining optical fibre 1-1-2 with LD, the 3rd polarization maintaining optical fibre 1-2-1 with LD and the 4th polarization maintaining optical fibre 1-2-2 institutes with LD
Quantum signal energy size is introduced, it is eventually through energy back information that the energy adjustment of 4 road emergent lights is consistent.
Described BB84 polarization encoders module (1) is by the first polarization maintaining optical fibre 1-1-1 with LD, the second polarization maintaining optical fibre with LD
1-1-2, the 3rd polarization maintaining optical fibre 1-2-1 with LD and the 4th polarization maintaining optical fibre 1-2-2 with LD, the first wollaston prism 1-1,
Two wollaston prism 1-2, depolarization BS1-3, collimation lens 1-4 and PIN pipe 1-5 compositions.First wollaston prism 1-1 will
The two beam crossed polarized lights that the first polarization maintaining optical fibre 1-1-1 with LD, the second polarization maintaining optical fibre 1-1-2 with LD are exported carry out conjunction beam；
The second described wollaston prism 1-2 is defeated by the 3rd polarization maintaining optical fibre 1-2-1 with LD, the 4th polarization maintaining optical fibre 1-2-2 with LD
The two beam crossed polarized lights gone out carry out conjunction beam；Closed simultaneously by the first wollaston prism 1-1, the second wollaston prism 1-2
2 kinds of crossed polarized lights of beam carry out conjunction beam by depolarization BS1-3, are protected by rotating 1-145 ° of transmission end wollaston prism
45 ° of polarization direction deviation between transmitted light and reflected light is demonstrate,proved, ensures that 4 road polarised lights are inclined with 0 °, 90 ° ,+45 ° and -45 ° of lines respectively
Shake direction outgoing, so as to ensure the coding output of 4 kinds of polarization states, finally send collimated light beam after collimation lens 1-4, and PIN
Pipe 1-5 is used to detect four tunnel luminous powers.
Described beam collimation device 2 is made up of coupled lens 2-1, single-mode fiber 2-2 and collimation diversing lens 2-3.
The directional light that BB84 polarization encoders module 1 exports, is coupled in single-mode fiber 2-2, then pass through after first passing around coupled lens 2-1
Collimate diversing lens 2-3 collimation outputs.
Described BB84 polarizes decoder module 8 by the first multimode fibre 8-1-1 with detector, more than second with detector
Mode fiber 8-1-2, the 3rd multimode fibre 8-2-1 with detector and the 4th multimode fibre 8-2-2 with detector, the 3rd wet drawing
This prism 8-1, the 4th wollaston prism 8-2, depolarization BS8-3, convergent lens 8-4 compositions.Part outgoing beam passes through
Polarization-maintaining, which is cut after light microscopic 7 reflects, to be entered in BB84 decoder modules 8, first passes around convergent lens 8-4 convergences, depolarization is passed through in converging light
BS8-3 is divided into transmission and reflection two-way, and transmitted light is introduced separately to band after the 3rd wollaston prism 8-1 polarization spectros and visited
Survey in the first multimode fibre 8-1-1, the second multimode fibre 8-1-2 with detector of device and detected, reflected light passes through the 4th
The 3rd multimode fibre 8-2-1 with detector, the with detector the 4th are introduced separately to after wollaston prism 8-2 polarization spectros
Detected in multimode fibre 8-2-2；Ensure transmitted light by rotating 8-145 ° of the 3rd wollaston prism of transmission end simultaneously
45 ° of polarization direction deviation between reflected light, so as to ensure 4 road polarised lights respectively with 0 °, 90 ° ,+45 ° and -45 ° linear polarization point
Amount is monitored.
Claims (6)
1. a kind of coaxial free space quantum communications code device in four tunnel, including BB84 polarization encoders module (1), light beam coupling
Device (2), the first rotatable quarter wave plate (3), the second rotatable quarter wave plate (4), rotatable 1/2 wave plate (5), beam expanding lens (6),
Polarization-maintaining cuts light microscopic (7), BB84 polarization decoder modules (8), it is characterised in that：
BB84 polarization encoders module (1) passes through the first polarization maintaining optical fibre (1-1-1) with LD, the second polarization maintaining optical fibre (1-1- with LD
2), the 3rd polarization maintaining optical fibre (1-2-1) with LD and the 4 road quantum signals of introducing of the 4th polarization maintaining optical fibre (1-2-2) with LD, described 4
Most of light in the quantum signal of road is inclined with 0 °, 90 ° ,+45 ° and -45 ° 4 kinds of lines respectively after BB84 polarization encoders module (1)
Light coaxially exports, and 4 kinds of line polarisations export after light beam coupling device (2) collimation again, and 4 road collimated lights of output are respectively by the
One rotatable quarter wave plate (3), the second rotatable quarter wave plate (4), rotatable 1/2 wave plate (5), beam expanding lens (6) are launched afterwards, wherein
Beam expanding lens (6) is used to compress the emergent light angle of divergence, while expands emergent light spot size；
Fraction light in the quantum signal of 4 road enters BB84 polarization decoder modules after polarization-maintaining cuts light microscopic (7) reflection
(8), BB84 polarizes decoder module (8) and the polarization of 0 °, 90 ° ,+45 ° and -45 ° of the polarised light that enter to inside modules can be divided
Amount measures simultaneously, and then monitors outgoing light polarization state, by the measurement to being emitted light polarization state, is entered using wave plate group
Row state of polarization auto compensation ensures the polarization state of emergent light；The first polarization maintaining optical fibre (1-1-1) with LD, second with LD protect simultaneously
Polarisation fibre (1-1-2), the 3rd polarization maintaining optical fibre (1-2-1) with LD and the 4th polarization maintaining optical fibre (1-2-2) introduced quantum with LD
The big I of signal energy is fed back as the signal received by BB84 decoder modules (8), is gone out 4 tunnels by energy back information
The energy adjustment for penetrating light is consistent.
A kind of 2. coaxial free space quantum communications code device in four tunnel according to claim 1, it is characterised in that：Institute
The BB84 polarization encoders module (1) stated is by the first polarization maintaining optical fibre (1-1-1) with LD, the second polarization maintaining optical fibre (1-1- with LD
2), the 3rd polarization maintaining optical fibre (1-2-1) with LD and the 4th polarization maintaining optical fibre (1-2-2), the first wollaston prism (1- with LD
1), the second wollaston prism (1-2), depolarization BS (1-3), collimation lens (1-4) and PIN pipes (1-5) composition；
Described the first wollaston prism (1-1) is by the first polarization maintaining optical fibre (1-1-1) with LD, the second polarization maintaining optical fibre with LD
The two beam crossed polarized lights of (1-1-2) output carry out conjunction beam；Described the second wollaston prism (1-2) protects the 3rd with LD
The two beam crossed polarized lights that polarisation fibre (1-2-1), the 4th polarization maintaining optical fibre (1-2-2) with LD export carry out conjunction beam；Described disappears
Polarization BS (1-3) possesses polarization-maintaining function, and 0 °, 90 ° ,+45 ° and -45 line polarisations are better than by depolarization BS (1-3) extinction ratio
2000：1, while by the first wollaston prism (1-1), 2 kinds of crossed polarized lights of the second wollaston prism (1-2) conjunction beam
Conjunction beam is carried out by depolarization BS (1-3), ensures transmitted light by rotating 45 ° of the wollaston prism of transmission end first (1-1)
45 ° of polarization direction deviation between reflected light, ensure 4 road polarised lights respectively with 0 °, 90 ° ,+45 ° and -45 ° line folk prescription to direction
Outgoing, while collimated light beam is sent after collimation lens (1-4), and PIN pipes (1-5) are used to detect four tunnel luminous powers.
A kind of 3. coaxial free space quantum communications code device in four tunnel according to claim 1, it is characterised in that：Institute
The light beam coupling device (2) stated is made up of coupled lens (2-1), single-mode fiber (2-2) and collimation diversing lens (2-3)；BB84
The directional light of polarization encoder module (1) output, it is coupled to after first passing around coupled lens (2-1) in single-mode fiber (2-2), then passes through
Cross collimation diversing lens (2-3) collimation output.
4. a kind of coaxial free space quantum communications code device in four tunnel according to claim 1 is characterized in that：Institute
The first rotatable quarter wave plate (3) for stating, the second rotatable quarter wave plate (4), rotatable 1/2 wave plate (5) can be in incident lights
Normal surface internal rotation, its phase delay precision are superior to 1/300 λ at using wavelength.
A kind of 5. coaxial free space quantum communications code device in four tunnel according to claim 1, it is characterised in that：Institute
The polarization-maintaining stated cuts light microscopic (7) and cuts angular less than 25 °, it is desirable to which+45 ° are better than 5000 with the extinction ratio after -45 ° of line polarisations reflections：
1。
A kind of 6. coaxial free space quantum communications code device in four tunnel according to claim 1, it is characterised in that：Institute
The BB84 polarization decoder modules (8) stated are by the first multimode fibre (8-1-1) with detector, the second multimode fibre with detector
(8-1-2), the 3rd multimode fibre (8-2-1) with detector and the 4th multimode fibre (8-2-2) with detector, the 3rd wet drawing
This prism (8-1), the 4th wollaston prism (8-2), the depolarization BS (8-3) in BB84 polarization decoder modules, convergence are saturating
Mirror (8-4) forms；
Part outgoing beam enters in BB84 decoder modules (8) after polarization-maintaining cuts light microscopic (7) reflection, first passes around convergent lens
(8-4) is assembled, and converging light is divided into transmission and reflection two-way by depolarization BS (8-3), and transmitted light passes through the 3rd Wollaston rib
The first multimode fibre (8-1-1) with detector, the second multimode light with detector are introduced separately to after mirror (8-1) polarization spectro
Detected in fine (8-1-2), reflected light is introduced separately to band detection after the 4th wollaston prism (8-2) polarization spectro
The 3rd multimode fibre (8-2-1), the 4th multimode fibre (8-2-2) with detector of device are interior to be detected；Described depolarization
BS (8-3) possesses polarization-maintaining function, and 0 °, 90 ° ,+45 ° and -45 line polarisations polarize the depolarization BS (8- in decoder module by BB84
3) extinction ratio after is better than 2000：1, while ensure transmitted light by rotating 45 ° of the 3rd wollaston prism (8-1) of transmission end
45 ° of polarization direction deviation between reflected light, carried out respectively with 0 °, 90 ° ,+45 ° and -45 ° direction so as to ensure 4 road polarised lights
Polarized component detects.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720603913.1U CN207010681U (en) | 2017-05-27 | 2017-05-27 | The coaxial free space quantum communications code device in four tunnels |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720603913.1U CN207010681U (en) | 2017-05-27 | 2017-05-27 | The coaxial free space quantum communications code device in four tunnels |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207010681U true CN207010681U (en) | 2018-02-13 |
Family
ID=61445443
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201720603913.1U Withdrawn - After Issue CN207010681U (en) | 2017-05-27 | 2017-05-27 | The coaxial free space quantum communications code device in four tunnels |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN207010681U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107147442A (en) * | 2017-05-27 | 2017-09-08 | 中国科学院上海技术物理研究所 | A kind of coaxial free space quantum communications code device in four tunnel |
| CN112217575A (en) * | 2019-07-12 | 2021-01-12 | 科大国盾量子技术股份有限公司 | Method and system for calibrating light intensity ratio of decoy state optical signal and signal state optical signal |
-
2017
- 2017-05-27 CN CN201720603913.1U patent/CN207010681U/en not_active Withdrawn - After Issue
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107147442A (en) * | 2017-05-27 | 2017-09-08 | 中国科学院上海技术物理研究所 | A kind of coaxial free space quantum communications code device in four tunnel |
| CN107147442B (en) * | 2017-05-27 | 2023-05-05 | 中国科学院上海技术物理研究所 | Four-way coaxial free space quantum communication coding device |
| CN112217575A (en) * | 2019-07-12 | 2021-01-12 | 科大国盾量子技术股份有限公司 | Method and system for calibrating light intensity ratio of decoy state optical signal and signal state optical signal |
| CN112217575B (en) * | 2019-07-12 | 2022-02-11 | 科大国盾量子技术股份有限公司 | Method and system for calibrating light intensity ratio of decoy state optical signal and signal state optical signal |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107147442A (en) | A kind of coaxial free space quantum communications code device in four tunnel | |
| US6061167A (en) | Optical isolator | |
| CN102175430B (en) | Device and method for measuring 1/8 wave plate phase retardation and fast axis azimuth angle | |
| CN207010681U (en) | The coaxial free space quantum communications code device in four tunnels | |
| CN102243104A (en) | Device for measuring properties of polarized light in real time | |
| CN104216050A (en) | Polarization beam splitting and combining device | |
| CN202033175U (en) | Measuring device of phase retardation and fast axis azimuth of one-eighth wave plate | |
| CN103033478A (en) | Double refraction realtime measuring device and method | |
| CN115001593B (en) | Hybrid integrated receiving chip for quantum key distribution | |
| CN102288294A (en) | Amplitude division measuring instrument and measuring method for polarization Stokes parameters | |
| CN104158161A (en) | Differential protection device based on optics current sensors | |
| CN115801117A (en) | Novel laser communication receiving and transmitting light beam integrated monitoring system and monitoring method | |
| CN102981268B (en) | Birefringent crystal beam splitter with adjustable lateral shearing quantity | |
| CN103954827A (en) | Optical current sensor | |
| CN104317072A (en) | Faraday rotating lens irrelevant to wavelength and temperature | |
| CN107919912B (en) | Same-frequency-band polarization multiplexing spatial laser communication optical transmitter and receiver | |
| CN104897368A (en) | Real-time polarization maintaining fiber extinction ratio testing device | |
| CN105375989A (en) | Free-space quantum communication device and method having real-time polarization compensation | |
| CN114650133B (en) | Polarization encoding device for quantum key distribution and quantum key distribution system | |
| CN107741244B (en) | M-Z interference light path structure with full polarization maintaining function | |
| CN106772837B (en) | The optical axis stable device of light beam coupling | |
| CN103728697A (en) | Three-port optical circulator | |
| CN205249238U (en) | Free space quantum communication device that possesses compensation of real -time polarization | |
| CN104038291A (en) | Integrated demodulation receiver | |
| US10948342B2 (en) | Bell state measurement apparatus based on single-mode optical fiber |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20180213 Effective date of abandoning: 20230505 |
|
| AV01 | Patent right actively abandoned |
Granted publication date: 20180213 Effective date of abandoning: 20230505 |
|
| AV01 | Patent right actively abandoned | ||
| AV01 | Patent right actively abandoned |