Ion trap device and quantum computing equipment

Abstract

The utility model provides an ion trap device and quantum computing equipment comprising the ion trap device, and the ion trap device comprises an ion trap; the cavity is used for sealing the ion trap; the plane window is arranged on the side wall of the cavity; the composite reflecting mirror is arranged in the cavity and is concave towards the plane window, the composite reflecting mirror comprises a parabolic reflecting mirror and a spherical reflecting mirror, the curvature radius of the spherical reflecting mirror is twice of the focal length of the spherical reflecting mirror, and ions trapped in the ion trap are arranged at the curvature center of the spherical reflecting mirror; the diffraction limit aspherical lens is arranged on the side, close to the plane window, in the cavity, and the composite reflector, the ion and the diffraction limit aspherical lens are coaxially arranged. By using the ion trap device provided by the utility model, the fluorescence collection efficiency of the ion trap can be improved without using an objective lens, and for quantum computing equipment, more accurate, more reliable and more efficient quantum computing can be realized.

Description

Technical Field

[0001] The utility model relates to the technical field of quantum computers, in particular to an ion trap device and a quantum computing device including the ion trap device. Background Art

[0002] At present, the research and development and application of ion trap-based quantum computers are being accelerated. Such a quantum computing device mainly uses an ion trap to trap ions and manipulate their quantum states to achieve the storage and manipulation of qubits. At the same time, it also uses quantum entanglement to achieve quantum parallel computing and quantum state transmission, and reads the state of the qubit by measuring the physical properties of the ions, so as to complete the quantum computing task. Since reading the state of the qubit is a necessary step in the output of quantum computing, it is necessary to collect the fluorescent photons emitted by the ions from the ion trap. Summary of the Invention

[0003] The purpose of the utility model is to provide an ion trap device and a quantum computing device including the ion trap device.

[0004] The utility model provides an ion trap device, which includes: an ion trap; a cavity for sealing the ion trap; a planar window arranged on the side wall of the cavity; a compound reflector arranged inside the cavity and concave towards the planar window, the compound reflector includes a parabolic reflector and a spherical reflector formed in the center of the parabolic reflector, the center of curvature of the spherical reflector coincides with the focus of the parabolic reflector, and the radius of curvature of the spherical reflector is twice the focal length of the spherical reflector, and the ions trapped in the ion trap are arranged at the center of curvature of the spherical reflector; a diffraction-limited aspherical lens arranged on one side close to the planar window inside the cavity, wherein the compound reflector, the ions and the diffraction-limited aspherical lens are coaxially arranged.

[0005] Preferably, the ions radiate fluorescence into the surrounding space with equal probability at a solid angle of 4π.

[0006] Preferably, the aperture of the spherical reflector is adapted to the aperture of the diffraction-limited aspherical lens.

[0007] Preferably, the distance between the ions and the diffraction-limited aspherical lens is the focal length of the diffraction-limited aspherical lens.

[0008] Preferably, the ions are one of ytterbium ions, calcium ions and barium ions.

[0009] Preferably, the ion trap is one of a blade trap, a quadrupole trap and a needle trap.

[0010] Preferably, the composite mirror is made of one of fused quartz, sapphire, ceramic, and stainless steel.

[0011] Preferably, the surface of the spherical mirror is coated with a reflective film for enhancing the reflection of fluorescence.

[0012] Preferably, the surface of the spherical mirror and the surface of the diffraction-limited aspherical lens facing the ion side are coated with indium tin oxide film for reducing charge accumulation.

[0013] The present utility model also provides a quantum computing device, which includes the ion trap device as described above.

[0014] The present utility model can improve the fluorescence collection efficiency of the ion trap to more than twice without using an objective lens. For a quantum computing device, the present utility model can significantly improve the accuracy and efficiency of quantum state detection, thereby improving the fidelity of qubit state reading, enhancing the coherence of qubits, improving the fidelity of quantum gate operations, and accelerating its quantum computing process, etc., which will contribute to achieving more accurate, reliable, and efficient quantum computing. Description of the Drawings

[0015] Through the following description in conjunction with the drawings, the above objects and features of the present utility model will become clearer.

[0016] Figure 1 The structural schematic diagram of the ion trap device of the present utility model is shown. Detailed Embodiments

[0017] Hereinafter, the embodiments of the present utility model will be described in detail with reference to the drawings.

[0018] Refer to Figure 1 , the ion trap device of the present utility model at least includes an ion trap (not shown in the figure), a cavity 101, a planar window 102, a composite mirror 103, and a diffraction-limited aspherical lens 104.

[0019] In Figure 1In the illustrated ion trap device, the cavity 101 is used to seal the ion trap (not shown in the figure); the planar window 102 is disposed on the sidewall of the cavity 101; the compound mirror 103 is disposed inside the cavity 101 and concave towards the planar window 102. The compound mirror 103 includes a parabolic mirror 1030 and a spherical mirror 1031 formed at the center of the parabolic mirror 1030. The center of curvature of the spherical mirror 1031 coincides with the focus of the parabolic mirror 1030, and the radius of curvature of the spherical mirror 1031 is twice the focal length of the spherical mirror 1031. The ions 100 trapped in the ion trap are disposed at the center of curvature of the spherical mirror 1031; the diffraction-limited aspherical lens 104 is disposed inside the cavity 101 on the side close to the planar window 102. Among them, the compound mirror 103, the ions 100, and the diffraction-limited aspherical lens 104 are coaxially arranged. The coaxial arrangement can ensure that the collected fluorescence is transmitted along the same optical axis, optimizing the focusing effect of the fluorescence, thereby reducing stray light in the optical path, improving the collection efficiency and focusing quality of the fluorescence, and achieving efficient photon collection.

[0020] In Figure 1 In the illustrated ion trap device, the fluorescence emitted by the ions 100 trapped in the ion trap can be collected by the compound mirror 103 on the left and the planar window 102 on the right respectively. Since the ions 100 trapped in the ion trap are disposed at the center of curvature of the spherical mirror 1031, the fluorescence radiated by the ions 100 within the aperture range of the spherical mirror 1031 on the left can be reflected back to the ions 100 along the original path by the spherical mirror 1031, and coincides with the fluorescence radiated by the ions 100 within the aperture range of the diffraction-limited aspherical lens 104 on the right. Together, they are collimated into parallel light perpendicular to the planar window 102 by the diffraction-limited aspherical lens 104 on the right, and then transmitted through the planar window 102 to a light detection device (not shown in the figure) for detection; at the same time, the fluorescence radiated by the ions within the aperture range of the parabolic mirror 1030 can be directly reflected by the parabolic mirror 1030 into parallel light perpendicular to the planar window 102, and then transmitted through the planar window 102 to the light detection device for detection.

[0021] Therefore, by using the ion trap device provided by the present utility model, not only can the fluorescence emitted by the ions trapped in the ion trap towards the window side be collected, but also the fluorescence emitted by the ions towards the other side opposite to the window can be collected, increasing the fluorescence collection efficiency of the ion trap to more than twice. In addition, by using the ion trap device provided by the present utility model, it is also possible to make the collected fluorescence vertically enter the planar window from inside the cavity, minimizing the light loss caused by the refraction of the collected fluorescence when passing through the planar window, thereby further improving the fluorescence collection efficiency of the ion trap.

[0022] In Figure 1In the illustrated ion trap device, the ion trap can be sealed in a cryogenic ultra-high vacuum environment inside the cavity. This vacuum environment helps to improve the performance, stability, and application scope of the ion trap.

[0023] In Figure 1 In the illustrated ion trap device, the ion 100 can radiate fluorescence into the surrounding space with equal probability at a 4π solid angle. This can ensure that the fluorescence signal can cover a very large angular range, further improving the fluorescence collection efficiency of the ion trap.

[0024] In Figure 1 In the illustrated ion trap device, the aperture of the spherical mirror 1031 in the compound mirror 103 can be adapted to the aperture of the diffraction-limited aspherical lens 104 to reduce the loss of fluorescence during collection due to the mismatch of their apertures. For example, if the aperture of the spherical mirror is smaller than that of the diffraction-limited aspherical lens, then part of the fluorescence emitted by the ion towards the parabolic mirror will not be able to enter the planar window perpendicularly, resulting in light loss; conversely, if the aperture of the spherical mirror is larger than that of the diffraction-limited aspherical lens, then part of the fluorescence emitted by the ion towards the spherical mirror will also not be able to enter the planar window perpendicularly, which will also cause light loss.

[0025] In Figure 1 In the illustrated ion trap device, the distance between the ion 100 and the diffraction-limited aspherical lens 104 can be set to the focal length of the diffraction-limited aspherical lens 104. This can ensure that the fluorescence is accurately focused by the diffraction-limited aspherical lens, avoiding the loss of part of the energy of the fluorescence during collection due to scattering, diffraction, etc. caused by the deviation of the distance between the two from the focal length.

[0026] In Figure 1 In the illustrated ion trap device, the ion 100 can be a ytterbium ion, a calcium ion, a barium ion, or other particles suitable for being trapped in the ion trap, and this invention is not limited thereto. The ion trap for trapping the ion 100 can be a blade trap, a quadrupole trap, a needle electrode trap, or other types of ion traps, and this invention is also not limited thereto.

[0027] In Figure 1 In the illustrated ion trap device, the spherical mirror 1031 in the compound mirror 103 can be made of materials such as, but not limited to, fused quartz, sapphire, ceramic, and stainless steel. These materials each have their unique advantages. Fused quartz has high transparency and good ultraviolet transmittance, sapphire has high hardness and good thermal conductivity, ceramic materials have high purity and excellent ion storage capacity, and stainless steel has good stability and workability. The most suitable material can be selected according to the specific working environment requirements and conditions to prepare the spherical mirror.

[0028] In Figure 1 In the shown ion trap device, the surface of the compound mirror 103 can be coated with a reflective film for enhancing the reflection of fluorescence to further improve the fluorescence collection efficiency of the ion trap. In addition, the surface of the compound mirror 103 and the surface of the diffraction-limited aspherical lens 104 facing the ion 100 can also be coated with indium tin oxide (ITO) film for reducing charge accumulation to reduce the influence of the accumulated charges on the fluorescence collection efficiency and quality. The accumulation of these accumulated charges on the surface of the spherical mirror can form an electrostatic field, and this electrostatic field can interfere with the propagation of fluorescence photons, resulting in partial fluorescence photons being reflected, scattered or absorbed, thereby reducing the fluorescence collection efficiency.

[0029] The ion trap device provided by the present utility model can be applied to a quantum computing device that uses an ion trap to implement quantum bit storage and operation to improve the fluorescence collection efficiency of the ion trap. For a quantum computing device, the improvement of the fluorescence collection efficiency means that more fluorescence photons can be collected, thereby improving the accuracy and precision of the quantum bit state reading. This is crucial for performing quantum gate operations, implementing quantum algorithms, and verifying quantum computing results. In addition, the improvement of the fluorescence collection efficiency also means that enough fluorescence photons can be collected in a shorter time to determine the state of the quantum bit. This can significantly accelerate the reading speed of the quantum bit and further improve the execution efficiency of quantum computing. Furthermore, the improvement of the fluorescence collection efficiency helps to more accurately read the state of the quantum bit, thereby reducing the decrease in the quantum bit fidelity caused by reading errors. High-fidelity quantum bits are the basis for performing high-precision quantum computing and quantum error correction.

[0030] Therefore, using a quantum computing device including the present utility model can more accurately read the state of the quantum bit, reduce errors, improve the accuracy and reliability of quantum computing, and promote the development of quantum computing applications.

[0031] Although the present utility model has been shown and described with reference to the preferred embodiments, those skilled in the art should understand that various modifications and transformations can be made to these embodiments without departing from the spirit and scope of the present application defined by the claims.

Claims

1. An ion trap device, characterized in that: include: Ion trap; A cavity, used to seal the ion trap; A plane window is arranged on the side wall of the cavity; A composite reflector, arranged inside the cavity and concave toward the plane window, the composite reflector comprising a parabolic reflector and a spherical reflector formed in the center of the parabolic reflector, the center of curvature of the spherical reflector coincides with the focus of the parabolic reflector, and the radius of curvature of the spherical reflector is twice the focal length of the spherical reflector, and the ions trapped in the ion trap are arranged at the center of curvature of the spherical reflector; A diffraction-limited aspheric lens is arranged inside the cavity on one side close to the plane window. Wherein, the composite reflector, the ions and the diffraction-limited aspheric lens are coaxially arranged.

2. The device according to claim 1, characterized in that The ions radiate fluorescence with equal probability into the surrounding space at a solid angle of 4π.

3. The device according to claim 1, characterized in that The aperture of the spherical reflector is adapted to the aperture of the diffraction-limited aspheric lens.

4. The device according to claim 1, characterized in that The distance between the ions and the diffraction-limited aspheric lens is the focal length of the diffraction-limited aspheric lens.

5. The device according to claim 1, characterized in that The ion trap is one of a blade trap, a quadrupole trap and a needle trap.

6. The device according to claim 1, characterized in that The composite reflector is made of one of fused quartz, sapphire, ceramic and stainless steel.

7. The device according to claim 1, characterized in that The surface of the spherical reflector is coated with a reflective film for enhancing reflection of fluorescent light.

8. The device according to claim 1, characterized in that The surface of the spherical reflector and the surface of the diffraction-limited aspherical lens facing the ions are plated with a tin-doped indium oxide film for reducing charge accumulation.

9. A quantum computing device, characterized in that An ion trap device comprising any one of claims 1-8.

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