Ion addressing device and ion trap quantum computer

Abstract

The present application discloses an ion addressing device and an ion trap quantum computer. The ion addressing device includes: a diffraction beam splitter; a first lens group is used to converge the multiple beams of light split by the diffraction beam splitter to a multi-channel acousto-optic modulator; a multi-channel acousto-optic modulator, the spacing between the spots of two adjacent beams of light in the multiple beams of light converged to the multi-channel acousto-optic modulator is consistent with the spacing between two adjacent channels in a plurality of channels arranged linearly; a second lens group is used to amplify the multiple beams of light output after modulation by the multi-channel acousto-optic modulator; an achromatic doublet lens is used to collimate the amplified multiple beams of light into parallel light; an interval focusing mirror is used to focus the collimated multiple beams of light onto multiple ions arranged linearly trapped in an ion trap, respectively, and the spacing between the spots of two adjacent beams of light in the multiple beams of light focused to the ion trap is consistent with the spacing between two adjacent ions in the plurality of ions arranged linearly. The present application realizes the precise control of multiple quantum bits.

Description

Technical Field

[0001] The present application relates to the technical field of quantum computers, and in particular to an ion addressing device for an ion trap quantum computer and an ion trap quantum computer including the ion addressing device. Background Art

[0002] In this field, the research and development of quantum computers is accelerating. The realization of quantum computers depends on the preparation and manipulation of quantum bits (qubits, or quantum bits). Unlike classical bits that can only represent 0 or 1, quantum bits can be in a superposition state of 0 and 1, allowing parallel computing. Quantum bits can be associated with other bits through "entanglement", making the computing process more parallel and computationally powerful.

[0003] In ion trap-based quantum computer technology, in order to execute these quantum gates and quantum algorithms, it is usually necessary to manipulate multiple quantum bits individually. Therefore, it is necessary to build an ion addressing device that can control multiple quantum bits to realize the execution of ion trap quantum computers. Summary of the invention

[0004] In view of this, embodiments of the present application provide an ion addressing device for an ion trap quantum computer and an ion trap quantum computer including the ion addressing device to solve at least one technical problem.

[0005] The ion addressing device provided in the embodiment of the present application includes: a diffraction beam splitter, which is used to split a plurality of linearly arranged light beams from the light emitted by the light source; a first lens group, which is used to converge the plurality of light beams split by the diffraction beam splitter to a multi-channel acousto-optic modulator; a multi-channel acousto-optic modulator, which is used to receive the plurality of light beams converged to the multi-channel acousto-optic modulator into a plurality of linearly arranged channels in the multi-channel acousto-optic modulator for modulation, wherein the spacing between the light spots of two adjacent light beams in the plurality of light beams converged to the multi-channel acousto-optic modulator is consistent with the spacing between two adjacent channels in the plurality of linearly arranged channels; a second lens group, which is used to amplify the plurality of light beams output after modulation by the multi-channel acousto-optic modulator; an achromatic doublet lens, which is used to collimate the amplified plurality of light beams into parallel light; and a spaced focusing lens, which is used to focus the collimated plurality of light beams respectively on a plurality of ions trapped in an ion trap and arranged linearly, wherein the spacing between the light spots of two adjacent light beams in the plurality of light beams focused to the ion trap is consistent with the spacing between two adjacent ions in the plurality of linearly arranged ions.

[0006] Optionally, the spot size of each light beam in the multiple light beams converged into the multi-channel AOM conforms to the channel photosensitivity range of the multi-channel AOM, and the spot size of each light beam in the multiple light beams focused into the ion trap conforms to the Airy disk size.

[0007] Optionally, the diffraction beam splitter, the first lens group, the multi-channel acousto-optic modulator, the second lens group, the achromatic doublet lens and the spaced focusing mirror are coaxially arranged.

[0008] Optionally, the modulation comprises modulation of at least one of the frequency, phase and amplitude of the light.

[0009] Optionally, the ion addressing device further includes: one or more reflectors arranged between the light source and the diffraction beam splitter, for reflecting the light emitted by the light source to the diffraction beam splitter.

[0010] Optionally, the ion addressing device further comprises: a negative meniscus lens disposed between the second lens group and the achromatic doublet lens, for eliminating part of or all of the aberrations caused by the coaxial deviation.

[0011] Optionally, the first lens group includes a first plano-convex lens and a second plano-convex lens that are adjacently arranged.

[0012] Optionally, the amplification includes two-stage amplification.

[0013] Optionally, the second lens group includes a first-stage magnifying lens group and a second-stage magnifying lens group that are adjacently arranged, and the two-stage magnification includes a first-stage magnification of the first-stage magnifying lens group and a second-stage magnification of the second-stage magnifying lens group.

[0014] Optionally, the first-stage magnifying lens group includes two plano-convex lenses and one plano-concave lens which are arranged adjacent to each other in sequence.

[0015] Optionally, the second-stage magnifying lens group includes a plano-convex lens and a plano-concave lens that are adjacently arranged.

[0016] Optionally, the multiple beams of light generate multiple diffraction orders through the multi-channel acousto-optic modulator, and one of the multiple diffraction orders is used for the modulation.

[0017] Optionally, the spacing between the light spots of two adjacent light beams in the multiple light beams converged on the multi-channel acousto-optic modulator is between 800µm and 950µm; and / or the diameter of the light spot of each light beam in the multiple light beams converged on the multi-channel acousto-optic modulator is between 90µm and 135µm.

[0018] Optionally, the spacing between the spots of two adjacent light beams among the multiple light beams focused into the ion trap is between 3µm and 12µm; and / or the diameter of the spot of each light beam among the multiple light beams focused into the ion trap is between 1µm and 5µm.

[0019] Optionally, the plurality of ions include at least one of the following ions: ytterbium ions, calcium ions, and barium ions.

[0020] The ion trap quantum computer provided in the embodiment of the present application includes the ion addressing device as described above.

[0021] The ion addressing device and ion trap quantum computer provided in the present application can realize precise control of multiple quantum bits, as well as quantum gate operations and execution of quantum algorithms based on multiple quantum bits. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following briefly introduces the drawings in the embodiments of the present application.

[0023] Figure 1 It is a schematic diagram of the structure of the ion addressing device of an embodiment of the present application.

[0024] Figure 2 This is a schematic diagram of the effect of a light beam passing through an acousto-optic modulator to generate a diffracted light array.

[0025] Figure 3 It is another structural schematic diagram of the ion addressing device of an embodiment of the present application.

[0026] Figure 4 It is a schematic diagram of the three-dimensional layout of the optical path system of the ion addressing device of the embodiment of the present application in the simulation software.

[0027] Figure 5 Schematic diagram of the spot spacing and size at the multi-channel AOM of an embodiment of the present application.

[0028] Figure 6 It is a schematic diagram of the spot spacing and size at the center ion of the trap in an embodiment of the present application.

[0029] Figure 7 It is a schematic diagram of the energy levels of the 171Yb+ ion in the embodiment of the present application.

[0030] Figure 8 It is a schematic diagram of the stimulated Raman transition of the interaction between 171Yb+ ions with a three-level configuration and laser according to an embodiment of the present application. DETAILED DESCRIPTION

[0031] The following is a detailed explanation of the principles and spirit of the present application with reference to several exemplary or representative embodiments of the present application.

[0032] refer to Figure 1 An embodiment of the present application provides an ion addressing device, which includes: a diffraction beam splitter 101, a first lens group 102, a multi-channel acousto-optic modulator 103, a second lens group 104, an achromatic doublet lens 105 and a spaced focusing mirror 106.

[0033] The diffraction beam splitter 101 is used to split the light emitted by the light source 10 into a plurality of linearly arranged light beams.

[0034] The first lens group 102 is used to converge the multiple beams of light split by the diffraction beam splitter 101 to the multi-channel acousto-optic modulator 103 .

[0035] The multi-channel AOM 103 is used to receive the multiple light beams converged on the multi-channel AOM 103 into the multiple channels linearly arranged in the multi-channel AOM 103 for modulation respectively, wherein the spacing between the light spots of two adjacent light beams in the multiple light beams converged on the multi-channel AOM 103 is consistent with the spacing between two adjacent channels in the multiple channels linearly arranged.

[0036] The second lens group 104 is used to amplify the multiple beams of light output after being modulated by the multi-channel acousto-optic modulator 103 .

[0037] The achromatic doublet lens 105 is used to collimate the amplified multiple beams of light into parallel light.

[0038] The spaced focusing mirror 106 is used to focus the collimated multiple beams of light onto multiple ions 20 arranged linearly trapped in the ion trap, wherein the spacing between the light spots of two adjacent beams of light in the multiple beams of light focused on the ion trap is consistent with the spacing between two adjacent ions in the multiple ions 20 arranged linearly.

[0039] Using the embodiment of the present application, the diffraction beam splitter 101 can split multiple linearly arranged beams of light from the light source 10, and the multiple beams of light can be converged to the multi-channel acousto-optic modulator 103 through the first lens group 102, and respectively enter the multiple linearly arranged channels in the multi-channel acousto-optic modulator 103 to be modulated in each channel respectively, wherein, in order to improve the modulation effect, the spacing between the light spots of two adjacent beams of light in the split multiple beams of light should be consistent with the spacing between two adjacent channels in the multi-channel acousto-optic modulator 103, and the multiple beams of light output after modulation enter the second lens group 104 for amplification, and then collimate into parallel light through the achromatic doublet lens 105, and then enter the spaced focusing mirror 106 to be focused on the multiple linearly arranged ions 20 trapped in the ion trap, wherein the spacing between the light spots of two adjacent beams of light in the multiple beams of light focused on the multiple ions 20 is consistent with the spacing between two adjacent ions in the multiple ions 20, thereby realizing ion addressing.

[0040] The implementation process of the embodiment of the present application involves multi-beam focusing analysis design and the selection of optical components. An ion addressing optical path system is constructed according to the embodiment of the present application, which can be used to realize the manipulation of a single quantum bit. Based on this, quantum gate operations of single and multi-qubits and the execution of quantum algorithms can be realized. On this basis, the execution and control of an ion trap quantum computer can be realized.

[0041] In an embodiment of the present application, optionally, to ensure the modulation effect, the spot size of each light beam in the multiple light beams converged to the multi-channel acousto-optic modulator 103 must conform to the channel photosensitivity range of the multi-channel acousto-optic modulator 103; to ensure the addressing effect, the spot size of each light beam in the multiple light beams focused to the ion trap must conform to the Airy disk size.

[0042] In an embodiment of the present application, optionally, the diffraction beam splitter 101, the first lens group 102, the multi-channel acousto-optic modulator 103, the second lens group 104, the achromatic doublet lens 105 and the spaced focusing mirror 106 are coaxially arranged to constitute the required ion addressing device.

[0043] In an embodiment of the present application, optionally, the modulation performed by the multi-channel acousto-optic modulator 103 includes modulation of at least one of the frequency, phase and amplitude of the light, so that at least one of the frequency, phase and amplitude of the modulated light beam meets system requirements.

[0044] Among them, the acousto-optic modulator (AOM) is a device that uses the acousto-optic effect to load information onto an optical carrier. Figure 2 , a beam of light passing through an acousto-optic modulator (AOM) may generate a diffraction light array including, for example, 5 different diffraction orders. Taking the first order diffraction order as an example, the light beam of the first order diffraction order has a frequency offset relative to the original light beam. Assuming that the frequency of the original light beam is 1000MHz, the frequency of the first order diffraction order light beam after passing through the AOM is 1200MHz, indicating that the radio frequency (RF) frequency applied to the AOM is 200MHz. Multi-channel acousto-optic modulators, i.e., multi-channel AOMs, allow multi-channel modulation and multi-channel beam deflection.

[0045] In the embodiments of the present application, optionally, reference Figure 1 The ion addressing device may also include one or more reflectors 107 disposed between the light source 10 and the diffraction beam splitter 101 , for reflecting the light emitted by the light source 10 to the diffraction beam splitter 101 .

[0046] As an example, Figure 3 The embodiment shows a case where two reflectors 107 are included. The two reflectors 107 are arranged at a suitable angle so that the light emitted by the light source 10 reaches the second reflector 107 after being reflected by the first reflector 107 and enters the diffraction beam splitter 101 after being reflected by the second reflector 107 .

[0047] In the embodiments of the present application, optionally, reference Figure 1 and Figure 3The ion addressing device may also include a negative meniscus lens 108 disposed between the second lens group 104 and the achromatic doublet lens 105, which is used to eliminate part or all of the aberrations caused by the coaxial deviation. The negative meniscus lens may also be called a negative focal length meniscus lens, which includes two curved surfaces (a convex surface and a concave surface) with similar curvature radii. If the optical axis of the light source 10 is inconsistent with the optical axis of the system during the propagation of the light beam, aberrations may be caused. By setting the negative meniscus lens 108, at least part of the aberrations can be eliminated, thereby improving the accuracy of the ion addressing device.

[0048] Among them, the achromatic doublet lens is a lens formed by gluing two optical components, a positive low refractive index and a negative high refractive index, and the dispersion properties of the two types of glass are used to compensate for each other to achieve the purpose of achromatism. In addition, the spaced focusing lens reduces the reflection and scattering of the lens surface by leaving a certain interval between the two lenses, thereby improving the focusing effect.

[0049] In the embodiments of the present application, optionally, reference Figure 1 and Figure 3 The first lens group 102 includes a first plano-convex lens 1021 and a second plano-convex lens 1022 that are adjacently arranged. The two plano-convex lenses are used to converge the light beams split by the diffraction beam splitter 101 into the multi-channel acousto-optic modulator 103. The focal length and size of the two plano-convex lenses can be selected according to system requirements.

[0050] In the embodiment of the present application, optionally, the amplification includes two-stage amplification, that is, the second lens group 104 performs two-stage amplification on the light beam output by the multi-channel acousto-optic modulator 103 .

[0051] For example, the second lens group 104 includes a first-stage magnifying lens group and a second-stage magnifying lens group that are adjacently arranged, and the two-stage magnification includes a first-stage magnification of the first-stage magnifying lens group and a second-stage magnification of the second-stage magnifying lens group.

[0052] As an example, refer to Figure 3 , the first-stage magnifying lens group and the second-stage magnifying lens group are respectively as follows. The focal length, size, etc. of each lens can be selected according to the needs of the system. Among them, the first-stage magnifying lens group includes two plano-convex lenses 1041 and 1042 arranged adjacent to each other, and a plano-concave lens 1043. The second-stage magnifying lens group includes a plano-convex lens 1044 and a plano-concave lens 1045 arranged adjacent to each other.

[0053] In an embodiment of the present application, optionally, the multiple beams of light generate multiple diffraction orders through the multi-channel acousto-optic modulator 103, and one of the multiple diffraction orders is used for modulation.

[0054] As an example, during modulation, each of the linearly arranged multiple light beams can be modulated by the multi-channel acousto-optic modulator 103 to generate multiple diffraction orders, and the frequency offsets of different diffraction orders are different. The same diffraction order consistent with the target frequency is selected to form a new light beam array. For example, the positive first diffraction order is selected as the new light beam array (of course, the negative first order, zero order, positive and negative second order diffraction orders can also be selected according to needs) to achieve modulation of multiple light beams.

[0055] In the embodiment of the present application, as a non-limiting example, regarding the spot spacing of two adjacent light beams in the multiple light beams converged on the multi-channel AOM 103, the spacing between the light spots of two adjacent light beams in the multiple light beams converged on the multi-channel AOM 103 can be between 800µm and 950µm, so that the diameter of the light spot of each light beam in the multiple light beams converged on the multi-channel AOM 103 is between 90µm and 135µm, so as to ensure that the multiple light beams separated from the beams enter the corresponding channels in the multi-channel AOM 103 respectively for modulation.

[0056] In an embodiment of the present application, as a non-limiting example, regarding the spacing between the spots of two adjacent light beams in the multiple light beams focused on the ion trap, the spacing between the spots of two adjacent light beams in the multiple light beams focused on the ion trap can be between 3µm and 12µm, and the diameter of the spot of each light beam in the multiple light beams focused on the ion trap can be between 1µm and 5µm, so as to ensure that the modulated multiple light beams are respectively focused on the multiple ions in the ion trap.

[0057] In an embodiment of the present application, optionally, the plurality of ions include but are not limited to at least one of ytterbium ions, calcium ions, and barium ions.

[0058] For different ions, the appropriate device coating and wavelength can be selected according to the ion properties when constructing the optical path system. Through the tolerance analysis of the system assembly of the entire ion addressing device, the results show that the beam array can meet the experimental requirements of ion addressing after passing through a series of optical elements in the ion addressing device.

[0059] Based on at least one of the above embodiments of the present application, the light beam in the constructed ion addressing device is individually controlled by a multi-channel AOM driven by radio frequency. During operation, by modulating the appropriate addressing light beam, any single-qubit or multi-qubit gate operation can be theoretically achieved, for example, a single-qubit rotation gate (R-gate), a two-qubit entanglement gate (XX-gate), and the like.

[0060] The ion addressing device according to the embodiment of the present application can realize the manipulation of a single quantum bit, based on which the execution of quantum gates and quantum algorithms of a single quantum bit or multiple quantum bits can be realized, and ultimately the execution and control of an ion trap quantum computer can be realized.

[0061] In order to improve the overall stability of the optical path in the ion addressing device and make it more in line with the requirements of quantum manipulation on devices and space environment, in the embodiment of the present application, the ion addressing device may optionally include a rigid chamber, referring to Figure 3 , the reflecting mirror 107, the diffraction beam splitter 101, the first plano-convex lens 1021, the second plano-convex lens 1022, the multi-channel acousto-optic modulator 103, the plano-convex lens 1041, the plano-convex lens 1042, the plano-concave lens 1043, the plano-convex lens 1044, the plano-concave lens 1045, the negative meniscus lens 108 and the achromatic doublet lens 105 are located in the rigid chamber ( Figure 3 The light source 10 and the spaced focusing mirror 106 are located outside the rigid chamber.

[0062] For example, the optical element can be fixed in the rigid chamber by gluing, or the optical element can be connected and installed together by using a sleeve, and then fixed in the rigid chamber. The rigid chamber as an outer shell can protect the optical element, and the optical device can be integrated inside the cavity (for example, a stainless steel shell can be used to form a chamber). On the one hand, it can eliminate the complex structure of conventional pressure plates, columns, etc. that are fixed separately. On the other hand, it actually forms an overall modular design for the optical path system, which has good integration, can save space on the optical platform, and is convenient for short-distance movement and long-distance transportation, ensuring the stability of the system structure and performance, which is more in line with quantum computing-related experiments and research applications, especially suitable for experiments and quantum simulations based on ion trap quantum computing.

[0063] Optionally, the design of the rigid chamber may be specifically configured according to the optical device in the chamber. For example, one or more openings may be provided on the wall of the rigid chamber. Figure 3 (not shown) for the external cables or pipes of the multi-channel AOM 103 to pass through.

[0064] Further, in an embodiment of the present application, optionally, the interior of the rigid chamber is configured to be temperature-controlled so that the ion addressing device as a whole is adapted to the low-temperature environment required for quantum bit operation.

[0065] The implementation process of the embodiments of the present application involves multi-beam focusing analysis design and selection of optical components. A modular ion addressing device can be constructed according to at least one embodiment provided in the present application. The overall design of the system is scientific and reasonable. It utilizes various types of optical components and lenses, and most of the optical components are arranged as a whole inside a rigid chamber to form a highly integrated, modular addressing device. The entire device meets the experimental requirements of single-ion addressing and can be used to realize quantum bit manipulation. Therefore, it can not only be used as a single-ion addressing optical path system for ion trap quantum computers, but can also be used in various types of scientific research tasks with related needs, laying a solid foundation for realizing the execution and control of quantum computers.

[0066] To achieve the experimental conditions for ion addressing, optionally, the spacing between the light spots of two adjacent light beams in the multiple light beams converged on the multi-channel acousto-optic modulator can be made between 850µm and 950µm, so that the light spot diameter of each light beam in the multiple light beams converged on the multi-channel acousto-optic modulator is between 105µm and 130µm; in addition, the spacing between the light spots of two adjacent light beams in the multiple light beams focused on the ion trap can be made between 3µm and 9µm, so that the light spot diameter of each light beam in the multiple light beams focused on the ion trap is between 1µm and 4µm.

[0067] The above describes the implementation of the ion addressing device and the modular ion addressing device according to the embodiment of the present application through multiple embodiments. The following describes the specific operation process of the embodiment of the present application in detail based on specific examples.

[0068] For ease of understanding, the following specific embodiments will still be referred to. Figure 3 The device structure shown in the figure should be understood that the types, models, parameters, etc. of the optical components listed below are all types, models, and parameters used in the specific embodiments given in this article. In other embodiments of this application, optical components of other types, models, parameters, etc. can of course be selected as long as they meet the requirements of the optical path system of the ion addressing device. As an example, Figure 3 The types and models of optical components used in the examples are as follows.

[0069] The light source 10 may be, for example, but not limited to, a 355 nm all-solid-state mode-locked ultraviolet laser of model Paladin Compact 355-4000.

[0070] The reflector 107 may be, for example, but not limited to, a 45-degree reflector with a coating wavelength of 350-400 nm.

[0071] The diffraction beam splitter 101 may be, for example, but not limited to, a 1:6 diffraction optical element of model MS-385-UYA.

[0072] The plano-convex lens 1021 may be, for example, but not limited to, a lens of model LA4579-UV, which is made of ultraviolet fused quartz, has a diameter of Ø1 inch, a focal length of 300 mm, and is covered with an anti-reflection film in the 245-400 nm band.

[0073] The plano-convex lens 1022 may be, for example, but not limited to, a lens of model LA4579-UV, which is made of ultraviolet fused quartz, has a diameter of Ø1 inch, a focal length of 300 mm, and is covered with an anti-reflection film in the 245-400 nm band.

[0074] The multi-channel acousto-optic modulator 103 may be, for example, but not limited to, an optical device of model AOMC 250 / 16.

[0075] The plano-convex lens 1041 may be, for example, but not limited to, a lens of model LA1708-AN-BK7, which has a diameter of Ø1 inch, a focal length of 200 mm, and is covered with an anti-reflection film in the 350-700 nm band.

[0076] The plano-convex lens 1042 may be, for example, but not limited to, a lens of model LA1464-AN-BK7, which has a diameter of Ø1 inch, a focal length of 1000 mm, and is covered with an anti-reflection film in the 350-700 nm band.

[0077] The customized plano-concave lens 1043 can be made of, for example, but not limited to, JGS1 material, with a size of 25.4mm+0 / -0.1, a center thickness of 3mm±0.03, double-sided coating with an anti-reflection film of R<0.3%@355nm band, a surface aperture of 3 (0.5), a center deviation of 3 points, a curvature of -20mm, and a focal length of -42.011mm at a wavelength of 355nm.

[0078] The plano-convex lens 1044 may be, for example, but not limited to, a lens of model LA4158-UV, which is made of ultraviolet fused quartz, has a diameter of Ø1 inch, a focal length of 250 mm, and is covered with an anti-reflection film in the 245-400 nm band.

[0079] The customized plano-concave lens 1045 can be made of, for example, but not limited to, JGS1 material, with a size of 25.4mm+0 / -0.1, a center thickness of 3.5±0.03, and is covered with an anti-reflection film with R<0.3%@355nm band, a surface aperture of 3 (0.5), a center deviation of 3 points, a curvature of -19.5mm, and a focal length of -40.96mm at a wavelength of 355nm.

[0080] The negative meniscus lens 108 may be, for example, but not limited to, a lens of model LF4706-UV, which is made of ultraviolet fused silica, has a diameter of Ø1 inch, a focal length of -500.0 mm, and is covered with an anti-reflection film in the 245-400 nm band.

[0081] The achromatic doublet lens 105 may be, for example, but not limited to, a lens of model ACT508-300-A, which has a diameter of Ø2 inches, a focal length of 300 mm, and is covered with an anti-reflection film in the 400-700 nm band.

[0082] The spaced focusing lens 106 may be, for example, but not limited to, a lens of model 355nmFL47Q, the effective focal length of which is approximately 47 mm.

[0083] Figure 3 The interior of the stainless steel chamber is provided with a heating / cooling device to control the temperature inside the chamber. Figure 3 The side wall and / or bottom of the stainless steel chamber shown is also provided with one or more holes to introduce the water cooling tube of the multi-channel AOM 103 and the input / output cable of the radio frequency signal, so as to supply the RF signal to the multi-channel AOM 103. The size of the stainless steel chamber needs to be able to stably accommodate the modular addressing optical path, and the optical element lens can be fixed in the chamber, or the optical element can be connected with a sleeve and then fixed in the chamber.

[0084] For the embodiments of the present application, before implementation, software (such as Zemax software) can be used to simulate and analyze the entire optical path, referring to Figure 4 , schematically showing Figure 3 The three-dimensional layout diagram of the software simulation of the embodiment, the optical components are all on the same optical axis. Figure 5 and Figure 6 They are lens data at the multi-channel AOM 103 and the center ion of the trap. Through simulation analysis, it is found that the spot spacing and size at the multi-channel AOM 103 can meet the requirements of the multi-channel AOM 103 for the spot. Specifically, the spacing between the spots is about 900 microns (µm), and the geometric radius of the spot is about 60µm. Figure 5 As shown. By optimizing the curvature radius of the two plano-concave lenses, a better spot geometry radius and spacing can be obtained at the ion, which is smaller than the radius of the Airy disk (this also shows that the design of the entire system is close to the diffraction limit). The final spacing between the spots is about 6µm, and the geometric radius of the spots is about 1µm, as shown Figure 6 As shown. Then the tolerance analysis of the whole system assembly was performed, and the results showed that the system has a probability of more than 90% to meet the experimental requirements of single ion addressing. Based on this, in the research of ion trap quantum computing and quantum simulation, this modular ion addressing device can be applied to any scientific research tasks with relevant requirements.

[0085] The following briefly describes the working process of the embodiment of the present application. For ease of understanding, Figure 3 This description is given as an example, and it should be understood that in other embodiments of the present application, the same or similar operating methods are adopted.

[0086] First, the 355nm Raman beam is split into a Raman beam array by a diffraction beam splitter 101, and the beam array is formed into an equally spaced beam array (spacing of 900µm and beam diameter of 120µm) by a plano-convex lens 1021 and a plano-convex lens 1022, so as to match the requirements of the multi-channel acousto-optic modulator 103. Next, the beam array is modulated into a new beam array of the first-order diffraction order by the multi-channel acousto-optic modulator 103, and then undergoes two-stage amplification, wherein the plano-convex lens 1041, the plano-convex lens 1042 and the customized plano-concave lens 1043 form the first stage of amplification, and the plano-convex lens 1044 and the customized plano-concave lens 1045 form the second stage of amplification, wherein the negative meniscus lens 108 is used to improve the system aberration, and after the two-stage amplification, the beam is collimated into parallel light by the achromatic doublet lens 105, and finally the beam is focused onto the ion chain by the spacer focusing lens 106 (the final beam spacing is 6µm and the beam diameter is 2µm).

[0087] For greater clarity, this application also provides additional specific construction Figure 3 Other parameters that may be used when the target ion is 171Yb+ ion.

[0088] The distance from the diffraction beam splitter 101 to the front surface of the plano-convex lens 1021 is 90 nm, and the thickness of the plano-convex lens 1021 is 2.58 mm.

[0089] The distance from the rear surface of the plano-convex lens 1021 to the front surface of the plano-convex lens 1022 is 170.326 mm, and the thickness of the plano-convex lens 1022 is 2.58 mm.

[0090] The distance from the plano-convex lens 1022 to the internal crystal of the multi-channel AOM 103 is 131.523 mm.

[0091] The distance from the internal crystal of the multi-channel AOM 103 to the front surface of the plano-convex lens 1041 is 64 mm, and the thickness of the plano-convex lens 1041 is 2.78 mm.

[0092] The distance from the rear surface of the plano-convex lens 1041 to the front surface of the plano-convex lens 1042 is 25.573 mm, and the thickness of the plano-convex lens 1042 is 2.15 mm.

[0093] The distance from the rear surface of the plano-convex lens 1042 to the front surface of the customized plano-concave lens 1043 is 97.119 mm, and the thickness of the customized plano-concave lens 1043 is 3 mm.

[0094] The distance from the rear surface of the customized plano-concave lens 1043 to the front surface of the plano-convex lens 1044 is 170.05 mm, and the thickness of the plano-convex lens 1044 is 2.7 mm.

[0095] The distance from the rear surface of the plano-convex lens 1044 to the front surface of the customized plano-concave lens 1045 is 60.75 mm, and the thickness of the customized plano-concave lens 1045 is 3.5 mm.

[0096] The distance between the rear surface of the custom-made plano-concave lens 1045 and the front surface of the negative meniscus lens 108 is 1 mm, and the thickness of the negative meniscus lens 108 is 3.5 mm.

[0097] The distance from the rear surface of the negative meniscus lens 108 to the front surface of the achromatic doublet lens 105 is 260.39 mm, and the thickness of the achromatic doublet lens 105 is 8.4+7 mm.

[0098] The distance from the rear surface of the achromatic doublet lens 105 to the front surface of the spaced focusing mirror 106 is 40 mm, and the effective focal length of the spaced focusing mirror 106 is 47 mm.

[0099] The distance from the rear surface of the spaced focusing mirror 106 to the ion chain is 32.689 mm.

[0100] It should be noted that the above-mentioned embodiments for constructing an ion addressing device are merely illustrative, and the present application is not limited thereto. As required, other parameters other than the above-mentioned parameters may be used to construct an ion addressing device.

[0101] The system of the present application belongs to multi-beam focusing analysis design and selection of optical components, and specifically involves an ion addressing device for an ion trap quantum computer. It should be understood that the focal length and spacing distance of each lens in the system, etc., can be set and adjusted according to needs without affecting the realization of the ion addressing function.

[0102] At least one of the above embodiments of the present application can be used to construct different types of ion addressing devices. In an ion trap quantum computer, the ion addressing device can be used to control multiple quantum bits, and then multiple quantum bits can be manipulated individually to execute related quantum gates and quantum algorithms. To help understand, as an example, Figure 7 The schematic diagram shows the energy level structure of the ytterbium ion, i.e., the 171Yb+ ion, where the ground state 2 S 1 / 2 The (F=0; mF=0) and (F=1; mF=0) hyperfine energy levels can form a quantum bit, where F is the total angular momentum quantum number, mF is the projection of the total angular momentum in the direction of the magnetic field (i.e., the magnetic quantum number), and the Qubit energy gap is 12642812118:466+δz2 Hz, where δz2=310.8×B2 is the Zeeman frequency shift of the second-order magnetic field, and B is the strength of the external static magnetic field.

[0103] Further, as an example, Figure 8The schematic diagram shows the stimulated Raman transition of the three-level configuration 171Yb+ ion interacting with the laser. During operation, the ion can be initialized by optical pumping, and then the S and P energy levels of the ion can be manipulated by 355nm laser to achieve the three-level configuration stimulated Raman transition, which can drive the coupling of the internal state (spin energy level) and external state (phonon energy level) of the ion. By using phonons as the medium, the entanglement operation of two quantum bits can be realized; then, combined with the flipping operation of a single quantum bit, a series of quantum gates can be realized; by combining different quantum gate operations, a series of quantum algorithms can be obtained.

[0104] It should be understood that the protection scope of the present application is not limited to this document. Any technician familiar with the technical field can think of some equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should be included in the protection scope of the present application.

Claims

1. An ion addressing device, characterized in that: include: A diffraction beam splitter is used to split the light emitted by the light source into multiple linearly arranged beams of light; A first lens group is used to converge the multiple beams of light split by the diffraction beam splitter to the multi-channel acousto-optic modulator, wherein the spacing between the light spots of two adjacent beams of light in the multiple beams of light converged to the multi-channel acousto-optic modulator is consistent with the spacing between two adjacent channels in the multiple channels arranged linearly; A multi-channel acousto-optic modulator, used to receive multiple beams of light converged on the multi-channel acousto-optic modulator into multiple channels linearly arranged in the multi-channel acousto-optic modulator for modulation respectively; The second lens group is used to amplify the multiple beams of light output after being modulated by the multi-channel acousto-optic modulator; Achromatic doublet lens, used to collimate the amplified multiple beams of light into parallel light; An interval focusing mirror is used to focus the collimated multiple beams of light onto multiple ions trapped in the ion trap and arranged linearly, wherein the spacing between the light spots of two adjacent beams of light in the multiple beams of light focused on the ion trap is consistent with the spacing between two adjacent ions in the multiple ions arranged linearly, and the light spot size of each beam of light in the multiple beams of light focused on the ion trap conforms to the size of the Airy disk; Wherein, the diffraction beam splitter, the first lens group, the multi-channel acousto-optic modulator, the second lens group, the achromatic doublet lens and the spacer focusing mirror are coaxially arranged; Wherein, The ion addressing device further comprises one or more reflectors arranged between the light source and the diffraction beam splitter, for reflecting the light emitted by the light source to the diffraction beam splitter; the first lens group comprises a first plano-convex lens and a second plano-convex lens arranged adjacent to each other; the ion addressing device further comprises a negative meniscus lens arranged between the second lens group and the achromatic doublet lens, for eliminating part or all of the aberrations caused by the coaxial deviation; the second lens group comprises a first-stage magnifying lens group and a second-stage magnifying lens group arranged adjacent to each other, the first-stage magnifying lens group comprises two plano-convex lenses and a plano-concave lens arranged adjacent to each other in sequence, and the second-stage magnifying lens group comprises a plano-convex lens and a plano-concave lens arranged adjacent to each other; The ion addressing device also includes a rigid chamber, wherein a reflector, a diffraction beam splitter, a first plano-convex lens, a second plano-convex lens, a multi-channel acousto-optic modulator, a first-stage magnifying lens group, a second-stage magnifying lens group, a negative meniscus lens, and an achromatic doublet lens are located in the rigid chamber; The light source and the spaced focusing mirror are located outside the rigid chamber; The interior of the rigid chamber is configured to be temperature controlled.

2. The device according to claim 1, characterized in that The spot size of each beam of light among the multiple beams of light converged into the multi-channel acousto-optic modulator conforms to the channel photosensitivity range of the multi-channel acousto-optic modulator.

3. The device according to claim 1, characterized in that The modulation includes modulation of at least one of the frequency, phase and amplitude of the light.

4. The device according to claim 1, characterized in that The amplification includes two stages of amplification.

5. The device according to claim 4, characterized in that The two-stage magnification includes a first-stage magnification of the first-stage magnification lens group and a second-stage magnification of the second-stage magnification lens group.

6. The device according to claim 1, characterized in that The multiple beams of light generate multiple diffraction orders through the multi-channel AOM, and one of the multiple diffraction orders is used for the modulation.

7. The device according to claim 1, characterized in that The spacing between the light spots of two adjacent light beams in the multiple light beams converged on the multi-channel acousto-optic modulator is between 800 μm and 950 μm; and / or the diameter of the light spot of each light beam in the multiple light beams converged on the multi-channel acousto-optic modulator is between 90 μm and 135 μm.

8. The device according to claim 1, characterized in that The spacing between the spots of two adjacent light beams in the multiple light beams focused on the ion trap is between 3 μm and 12 μm; and / or the diameter of the spot of each light beam in the multiple light beams focused on the ion trap is between 1 μm and 5 μm.

9. The device according to claim 1, characterized in that The plurality of ions include at least one of the following ions: ytterbium ions, calcium ions, and barium ions.

10. An ion trap quantum computer, characterized in that: include: The ion addressing device according to any one of claims 1 to 9.

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