Quantum reading system

Abstract

The invention provides a quantum reading system, and relates to the field of quantum computing. The quantum reading system comprises a vacuum shell, an ion trap, a laser device and a detection device; the ion trap is arranged in the vacuum shell and is used for constraining ions in the vacuum shell; the laser device is arranged outside the vacuum shell and is used for emitting detection light into the vacuum shell, and the detection light is used for inducing ions to radiate photons; the detection device comprises a plurality of detectors, and the plurality of detectors are arranged along the surface of the vacuum shell and used for collecting photons radiated by the ions. According to the invention, the plurality of detectors arranged along the surface of the vacuum shell surround the ions, so that the ions are surrounded after the solid angle collection ranges of each detector and the adjacent detector are combined, and the plurality of detectors collect photons radiated from all directions of the ions, thereby increasing the solid angle of the whole detection device for collecting the photons, and improving the detection efficiency. And the photon collection efficiency is improved, so that the influence on the quantum bit reading efficiency of ions is reduced.

Description

Technical Field

[0001] This application relates to the field of quantum computing, and particularly to a quantum readout system. Background Art

[0002] The computing unit of an ion trap quantum computing system is a qubit. The qubit is usually represented by the state of an ion, and the qubit information can be read out according to the state of the ion. The state of the ion can be manipulated by laser. Therefore, in the readout of qubit information, the qubit information can be read by detecting the light emitted by the ion after being irradiated by the laser. Specifically, when the ion is trapped in a vacuum environment and irradiated by the laser, it can induce the emission of fluorescent photons. The fluorescent photons corresponding to a certain solid angle can be collected and focused by a lens group, and then a photomultiplier tube (PMT) is used to count the collected fluorescent photons, and a charge coupled device (CCD) is used to convert the collected fluorescent photons into an image, and the qubit information in the current state of the ion is read according to the photon count or the image.

[0003] However, since the lens group has a low collection efficiency for photons, it is likely to affect the readout efficiency of qubit information. Summary of the Invention

[0004] This application provides a quantum readout system, which can improve the collection efficiency of photons and reduce the influence on the readout efficiency of qubit information.

[0005] An embodiment of this application provides a quantum readout system, including a vacuum housing, an ion trap, a laser device, and a detection device; the ion trap is arranged in the vacuum housing, and the ion trap is used to trap ions in the vacuum housing; the laser device is arranged outside the vacuum housing, and the laser device is used to emit detection light into the vacuum housing, and the detection light is used to induce the ions to radiate photons; the detection device includes a plurality of detectors, and the plurality of detectors are arranged along the surface of the vacuum housing, and the plurality of detectors are used to collect the photons radiated by the ions.

[0006] In this embodiment, when the ion trap traps ions and the detection light emitted by the laser device induces the trapped ions to radiate photons, the photons radiated by the ions are collected by a plurality of detectors arranged along the surface of the vacuum housing, and under the combination of the solid angle collection range of each detector and the solid angle collection range of adjacent detectors, the solid angle range formed by the plurality of detectors along the surface of the vacuum housing surrounds the ions, so that the plurality of detectors can collect the photons radiated by the ions from all directions, thereby increasing the solid angle of the entire detection device for collecting photons, improving the collection efficiency of photons, and thus reducing the influence on the readout efficiency of qubit information.

[0007] It should be noted that the solid angle is measured by the area intercepted by the conical surface on the spherical surface with a radius of 1 centered at the vertex of the cone, and the unit of measurement is called "steradian". Each detector is the center of the corresponding cone. The "steradian" intercepted by the spherical surface with a radius of 1 centered at the detector on the spherical surface by the conical surface is the solid angle range for each detector to collect photons. The solid angle range formed by the superposition and combination of multiple detectors surrounds the ion, enabling the solid angle for the entire detection device to collect photons to surround the ion in all 360-degree directions, thereby increasing the solid angle for the entire detection device to collect photons.

[0008] In some embodiments, the multiple detectors include multiple first detectors, and the multiple first detectors are located inside the vacuum housing and arranged along the inner surface of the vacuum housing. With this arrangement, when the material of the vacuum housing is metal, arranging the multiple detectors inside the vacuum housing and along the inner surface of the vacuum housing shortens the distance between the detectors and the trapped ions, increasing the steradian intercepted by the spherical surface with a radius of 1 centered at the detector on the spherical surface by the conical surface, which helps to increase the solid angle for the detectors to collect photons.

[0009] In some embodiments, the multiple detectors include multiple second detectors, and the multiple second detectors are located outside the vacuum housing and arranged along the outer surface of the vacuum housing. With this arrangement, when the material of the vacuum housing is glass, arranging the multiple detectors outside the vacuum housing and along the outer surface of the vacuum housing facilitates the installation of the multiple detectors outside the vacuum housing, reducing the installation difficulty of the multiple detectors, and can reduce the connection ports on the vacuum housing, which is beneficial to increasing the collection range of photons by the detectors.

[0010] In some embodiments, the multiple detectors are arranged around the vacuum housing for at least one full circle. With this arrangement, the vacuum housing is circumferentially surrounded by the multiple detectors, and thus the ion inside the vacuum housing is circumferentially surrounded by the multiple detectors, facilitating the collection of photons radiated by the ion in the circumferential direction by the multiple detectors.

[0011] In some embodiments, the at least one full circle of detectors arranged around the vacuum housing are equally spaced. With this arrangement, the multiple detectors are evenly distributed in the circumferential direction around the ion inside the vacuum housing, which helps to improve the collection efficiency of the detectors for photons.

[0012] In some embodiments, there is a gap between at least two of the detectors for the detection light emitted by the laser device to pass through. With this arrangement, even when the detection light emitted by the laser device is densely arranged with multiple detectors, it can still irradiate the ions inside the vacuum housing, which helps to increase the solid angle range for the detectors to collect photons and facilitates the detection light to induce the ions to radiate photons.

[0013] In some embodiments, the shape of the vacuum housing includes any one of a columnar body, a polyhedron, and a spherical body. Such a setting facilitates the uniform arrangement of multiple detectors on each surface of the vacuum housing, surrounding the ions in all directions within the vacuum housing, and helps the detectors form a dense array arrangement along the surface of the vacuum housing.

[0014] In some embodiments, the detection device further includes a filter disposed on the collection side of the detector, and the filter is used to filter out the detection light reflected by the ions. With such a setting, in the case where the ions not only radiate photons but also reflect the detection light, the detection light reflected by the ions is filtered out by the filter, reducing the detection light other than photons collected by the detector, which helps to reduce the influence on the photon counting result.

[0015] In some embodiments, the laser device includes at least two laser assemblies, the at least two laser assemblies include a first laser assembly and a second laser assembly, the first laser assembly is used to emit a first laser, and the second laser assembly is used to emit a second laser; the first laser and the second laser constitute the detection light emitted by the laser device; the sum of the energy levels of the first laser and the second laser is equal to the energy level required for the ions to induce the photons, and the frequencies of the first laser and the second laser are both lower than the frequency of the photons.

[0016] With such a setting, the first laser and the second laser are respectively emitted by the first laser assembly and the second laser assembly, so that the first laser and the second laser can be emitted simultaneously and irradiated onto the ions in the vacuum housing, facilitating the sum of the energy levels of the co-irradiation of the first laser and the second laser to reach the energy level required for the ions to induce photons, which helps to make the ions induce photons; and, since the frequencies of the first laser and the second laser are lower than the frequency of the photons, when collecting the photons, it is convenient to distinguish the first laser, the second laser from the photons, and then facilitate filtering out the first laser and the second laser reflected by the ions, which helps to improve the purity of the photons collected by the detector.

[0017] In some embodiments, the laser assembly includes a laser and an optical path device, and the optical path device is located on the light-emitting side of the laser, and the optical path device is used to direct the laser emitted by the laser towards the vacuum housing. With such a setting, when inducing the ions to radiate photons, since the laser emitted by the laser can be directed towards the vacuum housing through the optical path device, and the optical path device can change the emission direction of the laser, the direction and angle of the laser entering the vacuum housing can be changed again through the optical path device, thus facilitating the adjustment of the direction and angle of the laser entering the vacuum housing.

[0018] In some embodiments, the laser device further includes a radio frequency source and a radio frequency switch. The radio frequency switch is connected between the radio frequency source and the optical path device. The radio frequency switch is used to control the on / off of the radio frequency signal between the radio frequency source and the optical path device, and the optical path device is configured to conduct after receiving the radio frequency signal. With such an arrangement, by controlling the on / off of the radio frequency signal between the radio frequency source and the optical path device through the radio frequency switch, the radio frequency switch can control the time for the radio frequency signal to be conducted to the optical path device. Furthermore, the optical path device controls the duration of the laser beam directed at the vacuum housing according to the duration of the received radio frequency signal, thereby facilitating the control of the duration of the laser beam directed into the vacuum housing.

[0019] In some embodiments, the optical path device includes an optical path and a modulator. The optical path allows the probe light to pass through, and the modulator is disposed on the optical path. The modulator is connected to the radio frequency switch and is configured to control the optical path to conduct after receiving the radio frequency signal. With such an arrangement, when the radio frequency switch is turned on, the radio frequency signal is conducted to the modulator. After receiving the radio frequency signal, the modulator controls the optical path to conduct, so that the probe light emitted by the laser device can pass through the optical path and be directed into the vacuum housing. Furthermore, under the guidance of the optical path, the probe light passing through the optical path can be directed into the vacuum housing between two adjacent detectors, thereby facilitating the adjustment of the angle and direction of the probe light directed into the vacuum housing.

[0020] In some embodiments, the detection device further includes a data processor connected to the plurality of detectors; the quantum readout system further includes a control device connected to the data processor and the laser device. The control device is configured to control the laser device to emit laser light and to control the data processor to count the photons collected by the plurality of detectors.

[0021] With such an arrangement, by controlling the laser device and the data processor to work simultaneously through the control device, when the laser device emits the probe light, the data processor starts to count the photons collected by the detectors, so that the data processor can count the photons collected by the detectors within the same working time as the laser device, thereby facilitating the counting of the photons radiated by the ions during the period when the probe light irradiates the ions. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural block diagram of an ion trap quantum computing system provided by an embodiment of the present application;

[0023] Figure 2 It is a schematic diagram of the calculation process of an ion trap quantum computing system provided by an embodiment of the present application;

[0024] Figure 3 It is a schematic structural diagram of an ion trap quantum readout system provided by an embodiment of the present application;

[0025] Figure 4 For the embodiment of the present application 40 Ca + energy level structure diagram;

[0026] Figure 5 Schematic structural diagram of the ion trap vacuum chamber provided by the embodiment of the present application;

[0027] Figure 6 Schematic structural diagram of the single-photon avalanche photodetector provided by the embodiment of the present application;

[0028] Figure 7 For the embodiment of the present application, Sr + radiation laser energy level schematic diagram;

[0029] Figure 8 Block diagram of the quantum readout system provided by the embodiment of the present application;

[0030] Figure 9 Block diagram of the structure where multiple detectors are arranged inside the vacuum housing provided by the embodiment of the present application;

[0031] Figure 10 Schematic diagram of laser energy level transition of the background-free fluorescence technology provided by the embodiment of the present application;

[0032] Figure 11 Schematic diagram of the solid angle of the detector provided by the embodiment of the present application;

[0033] Figure 12 Axial schematic diagram of the detector layout in the blade trap provided by the embodiment of the present application;

[0034] Figure 13 Schematic diagram of 955 points of spherical close packing provided by the embodiment of the present application;

[0035] Figure 14 Block diagram of the structure where multiple detectors are arranged outside the vacuum housing provided by the embodiment of the present application;

[0036] Figure 15 Flowchart of the quantum readout method provided by the embodiment of the present application. Detailed implementation manners

[0037] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0038] In the description and claims of the present invention and in the above-mentioned drawings, terms such as "first", "second", etc. (if any) are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily limit to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0039] First, some concepts that may be involved in the embodiments of the present invention are briefly introduced below.

[0040] Energy level: A theory explaining the motion orbits of electrons outside the atomic nucleus. Electrons move in specific, discrete orbits, and electrons in each orbit have discrete energies, and these energy values are the energy levels. In other words, in an atom, each definite energy state of an electron is called an energy level, and an energy level can also be called an "energy state".

[0041] Ground state, excited state: The ground state is the state in which, under normal conditions, electrons in an atom move only in the energy level closest to the nucleus and with the lowest energy. This state of motion is called the ground state of the atom. The excited state is the state in which, in an atom, electrons receive energy and jump from a lower energy level to a higher energy level. This higher energy state is called the excited state. Using laser irradiation can cause the electrons of an atom to jump from the ground state to the excited state.

[0042] Solid angle: It is measured by the area of a spherical surface with a radius of 1 intercepted by a conical surface with the vertex of the cone as the center of the sphere. The unit of measurement is called a steradian.

[0043] Quantum computing: A new computing mode that follows the laws of quantum mechanics to control quantum information units for computing. In contrast to traditional general-purpose computers, the theoretical model is the universal Turing machine; for quantum computers, the theoretical model is the universal Turing machine reinterpreted by the laws of quantum mechanics. In terms of computing efficiency, due to the existence of quantum mechanical superposition, quantum computers are more efficient than general-purpose computers in solving certain problems.

[0044] Ion trap: A device for confining charged ions, which generally fixes the position of ions in space through a specific electromagnetic field.

[0045] Quantum state detection: Using a detector to detect the fluorescence emitted by ions after being excited, and then detecting quantum bits.

[0046] Quantum manipulation: Operating on qubits using external signals such as lasers or microwaves.

[0047] Lens group: In an optical system, a lens group is formed by combining lenses with different focal lengths according to a certain rule, which can achieve the collection and focusing of fluorescence.

[0048] Ion trap quantum computing system: A physical system for implementing quantum computing. It uses the states of ions trapped in a vacuum as qubits, and the readout of qubits is achieved by measuring the internal states of the ions. For example, the readout of qubits is completed by irradiating the ions with a laser and detecting the light reflected by the ions.

[0049] In an ion trap quantum computing system, for the part of qubit readout, a lens group is usually used to collect and focus the fluorescence photons of ions within a certain solid angle. It can be understood that after the laser irradiates the ions, the ions are converted from the ground state to the excited state and emit fluorescence. By collecting the fluorescence photons, the qubit information can be converted to complete the readout of qubit information.

[0050] For this reason, in some implementation manners, for the ion trap quantum computing system in detail, please refer to Figure 1 , Figure 1 which is the structural block diagram of the ion trap quantum computing system 1000 provided by the embodiment of the present application. The ion trap quantum computing system 1000 includes a control system 110, a laser system 120, an ion trapping system 130, a detection system 140, and a vacuum system 150. Among them, the control system 110 is respectively connected to the laser system 120, the ion trapping system 130, and the detection system 140 to facilitate the separate operation of the laser system 120, the ion trapping system 130, and the detection system 140.

[0051] The ion trapping system 130 is used to trap ions in the vacuum system 150, and the vacuum system 150 is used to provide a vacuum environment. The laser system 120 is used to cool the ions, prepare the initial state, perform quantum state operations, and induce the ions to radiate fluorescence photons in the vacuum system 150. The detection system 140 is used to collect fluorescence photons, and the control system 110 is used to count the collected fluorescence photons and read the quantum state information according to the fluorescence photon counting result.

[0052] Continue to refer to Figure 1, the vacuum system 150 includes a vacuum chamber 151. The ion trapping system 130 includes a trapping electromagnetic field generating device 131 and trap electrodes 132, and there is a target on the trap electrodes 132. The trapping electromagnetic field generating device 131 is located outside the vacuum chamber 151, and the trap electrodes 132 are located inside the vacuum chamber 151. They can be connected to the trap electrodes 132 through the flange interface on the vacuum chamber 151 to provide a strong magnetic field to the trap electrodes 132, so that the trap electrodes 132 generate a confinement electric field to confine ions in the vacuum chamber 151. It should be noted that the trapping electromagnetic field generating device 131 needs to create an environment of a strong magnetic field for the trap electrodes 132, which can be a voltage device that generates an alternating voltage of dozens of megahertz.

[0053] The laser system 120 includes a laser 121. The laser emitted by the laser 121 includes ablation light, ionization light, cooling light, pump light, manipulation light, and detection light. The laser 121 can be connected to the inside of the vacuum chamber 151 through the flange interface on the vacuum chamber 151, so that the laser 121 can irradiate the laser onto the trap electrodes 132. The detection system 140 includes a lens group located outside the vacuum chamber 151 and a detector. The detector is connected to the control system 110. The photons radiated by the ions are focused through the lens group, and the detector collects the focused photons, so that the control system 110 can count the collected photons.

[0054] In some implementation manners, refer to Figure 2 , Figure 2 is a schematic diagram of the calculation process of the ion trap quantum computing system 1000 provided by the embodiment of the present application. Different lasers are emitted by the laser system 120 to process and manipulate ions, mainly including steps S101 to S105:

[0055] S101, Atomic ionization. Ions or atoms can be ejected by irradiating the ablation light on the target of the trap electrodes 132, and then the outer electrons of the atoms are heated by the atomic furnace. Under the irradiation of the ionization light, the outer electrons of the atoms are ionized to form ions, so that the inside of the trap electrodes 132 is all ions;

[0056] S102, Trapping and cooling. The ions formed by ionization can be trapped by the trap electrodes 132, and then the ions are cooled by irradiating the cooling light onto the ions, so as to cool the external vibrational state of the ions to the ground state.

[0057] S103, Quantum state initialization. The internal quantum state of the ions can be initialized by irradiating the pump light onto the ions, and then the manipulation light is irradiated onto the ions, so that the manipulation light interacts with the ions to obtain a specific quantum state of the ions, completing the preparation of the initial state of the ions.

[0058] S104. Ions radiate photons. The detection light pulses of different frequencies, intensities, and lengths can be controlled by a control system to manipulate the ions, causing the ions to be induced and radiate fluorescent photons.

[0059] S105. Quantum state detection. The detection system 140 can collect and count the fluorescent photons radiated after the detection light irradiates the ions to obtain quantum state information.

[0060] It should be noted that after the quantum state of the ions is detected, the ions are irradiated again with the detection light, and the photons radiated by the ions are collected, and the process can start again from step S103.

[0061] Thus, it can be known that in the ion trap quantum computing system 1000, the part for reading out qubit information can include the trap electrode 132, the vacuum chamber 151, the laser 121, and the detector. To better read out the qubit information, the readout system 100 based on the ion trap is introduced below.

[0062] In some implementation manners, as Figure 3 shown, Figure 3 is a schematic structural diagram of the ion trap quantum readout system 100 provided by an embodiment of the present application. Figure 3 In it, the trap electrode 101 is located inside the vacuum chamber 102. The trap electrode 101 is used to confine ions and trap the ions. The lens group 103 is located on one side of the trap electrode 101 and is used to collect and focus the fluorescent photons radiated by the ions. The detector 104 includes a photomultiplier tube (PMT) or a charge-coupled device (CCD) on the side of the lens 103 facing away from the trap electrode 101. It can be known from Figure 3 that the lens group 103 and the PMT or CCD are located outside the vacuum chamber 102. The PMT is used to count the fluorescent photons collected and focused by the lens group 103, and the CCD is used to form an image of the fluorescent photons collected and focused by the lens group 103.

[0063] It should be noted that the PMT is a vacuum electron device that converts a weak light signal into an electrical signal and can measure the weak radiation power with a wavelength of 200 nm to 1200 nm, such as measuring the fluorescent photons radiated by ions. Therefore, it is commonly used as a fluorescent photon detector in atomic and molecular physics experiments. It should be noted that a single-channel PMT can be used for single-ion experiments, and a multi-channel PMT can be used for multi-ion experiments. The CCD is an image sensor that can convert light into charge, store and transfer the charge, and form an image. It is commonly used for ion observation and multi-ion fluorescence readout in the ion trap quantum readout system 100.

[0064] Since the readout of qubits requires the use of devices such as PMTs or CCDs to detect weak light, in order to improve the signal-to-noise ratio, it is necessary to minimize the stray light entering the detector 104. Generally, a lens group 103 is used to collect fluorescence. Because the lens group 103 not only has the functions of light collection, focusing, and imaging, but also has the function of blocking stray light, because only the light near the optical axis in the lens group 103 can finally reach the detector 104. For stray light with a large difference in wavelength or frequency from the fluorescence, it can be filtered out by adding a filter in the lens group 103.

[0065] In the readout of qubits, the ions can include 40 Ca + 、 88 Sr + 、 171 Yb + and can complete the readout of qubit information by irradiating the 40 Ca + 、 88 Sr + 、 171 Yb + plasma with probe light, radiating photons, and then counting the collected photons.

[0066] However, there are still cases where it is still difficult to filter out stray light using a filter. As shown in Figure 4 and Figure 4 is the energy level structure diagram of 40 Ca + provided by the embodiment of the present application. Since the trap electrode 101 often selects ions with a hydrogen-like energy level structure, the corresponding probe light and fluorescence usually correspond to the transition between the S-P energy levels. Therefore, in this embodiment, a 40 Ca + is taken as an example, and a red-detuned 393 nm laser is often used as the probe light. After irradiating the 393 nm probe light on the ions, the ions radiate 393 nm fluorescence. By collecting and counting the 393 nm fluorescence, qubit information can be obtained. And from Figure 4 it can be seen that the energy levels of the 729 nm, 866 nm, and 854 nm probe lights are all lower than the energy level of 393 nm. Therefore, the 393 nm probe light induces the best fluorescence radiation effect in the ions, but the frequencies of the 393 nm probe light and the 393 nm fluorescence are the same, and it is difficult to filter out using a filter.

[0067] Therefore, in order to reduce the stray light formed by the 393 nm probe light reflected by the ions collected, the collection of fluorescence needs to avoid the probe light. Please refer to Figure 3 and refer to Figure 4 together, Figure 3Schematic diagram of the ion trap quantum readout system 100 provided by an embodiment of the present application. Figure 4 Provided by an embodiment of the present application 40 Ca + Energy level structure diagram of ions. Taking the probe light of 729 nm as an example, the emission direction of the probe light and the optical axis direction of the lens group 103 for collecting fluorescence need to be perpendicular or at a certain angle to avoid the emission direction of the probe light being collinear with the optical axis of the lens group 103 for collecting fluorescence.

[0068] It should be noted that the collection efficiency of ion fluorescence is not only limited by the emission direction of the probe light and the collection direction of the lens group 103, but also limited by the trap electrode 101 and the vacuum chamber 102. It can be understood that on the one hand, if the structure of the trap electrode 101 is complex or too large, the distance between the ions and the lens group 103 will be relatively far, resulting in a smaller solid angle for the lens group 103 to collect ion fluorescence, and thus a lower fluorescence collection efficiency. On the other hand, as Figure 5 shown Figure 5 Schematic diagram of the ion trap vacuum chamber 102 provided by an embodiment of the present application. Figure 5 In this figure, the resonator 105 is connected to the metal vacuum chamber 102. The resonator 105 is used to apply a strong magnetic field to the trap electrode 101, so that the trap electrode 101 generates a confinement field to confine the ions. The resonator 105 and the trap electrode 101 are electrically connected through the flange structure on the metal vacuum chamber 102, and the ion pump and the vacuum gauge 106 are also connected to the metal vacuum chamber 102 through the flange structure to evacuate the vacuum chamber 102 and adjust the vacuum degree. It can be seen that installing a laser to irradiate the laser, the electrical connection of the resonator 105 and the trap electrode 101, and the vacuum connection of the ion pump and the vacuum gauge 106 on the metal vacuum chamber 102 will all occupy a certain number of flanges, resulting in a limited number of available windows for collecting fluorescence on the vacuum chamber 102. It is easy for most of the fluorescence radiated by the ions to hit the inner wall of the vacuum cavity and not be collected and utilized, resulting in a lower fluorescence collection efficiency.

[0069] Therefore, Figures 3 - 5The quantum bit readout method has the following defects: on the one hand, the solid angle for collecting fluorescence is limited by the lens group 103. It can be understood that the multiple groups of lenses in the lens group 103 result in a long distance between the lens and the ions, and the lens group 103 can only collect and focus photons radiated in one direction of the ions, resulting in a small solid angle. Even if a large numerical aperture (NA) lens is used, the proportion of collected fluorescence is difficult to exceed 10%; on the other hand, there are many flange interfaces on the metal vacuum cover 102, resulting in most of the fluorescent photons radiated by the ions hitting the inner wall of the vacuum cover 102 and not being collected; on the other hand, since the transmittance of the optical elements in the lens group 103 decreases with the increase in the number of lenses, the fluorescent photons will gradually attenuate after passing through the lens group 103, resulting in the loss of fluorescence during the collection process.

[0070] From this we can see that Figures 3 - 5 The quantum bit readout method has a low collection efficiency for fluorescent photons, which can be verified by the following formula:

[0071] For example, regarding the collection and focusing of fluorescent photons by the lens group 103 , considering that the typical NA value of the lens in the ion trap quantum readout system 100 does not exceed 0.6, 0.6 is selected.

[0072]

[0073] The above formula shows that the percentage of fluorescence collected by lens group 103 in ion trap quantum readout system 100 does not exceed 0.10. Considering that some fluorescence is lost when passing through lens group 103, we temporarily assume 15%. Finally, considering that the quantum efficiency of PMTs and CCDs is generally between 25% and 40%, we temporarily assume 30%, and the total collection efficiency is:

[0074]

[0075] It can be seen that the total collection efficiency of the lens group 103 does not exceed 3%. Figure 3 The efficiency of detecting and collecting fluorescent photons using the lens group 103 is low.

[0076] To prevent the lenses in lens group 103 from gradually attenuating the fluorescent photons, for example, see Figure 6 , Figure 6 The schematic diagram of the structure of the single-photon avalanche photodetector 107 provided in the embodiment of the present application is that the single-photon avalanche photodetector 107 is integrated near the surface well using modern micro-nano processing technology. + For example, Sr +It is bound at a position 50 μm away from the single-photon avalanche photodetector 107, so as to integrate radio frequency and DC voltage on the chip of the surface trap and the single-photon avalanche photodetector 107 in the ion trap quantum computing system 1000, making the entire single-photon avalanche photodetector 107 more integrated and smaller in volume. Figure 6 In [reference document], n+ uses materials such as AICu, Nb, SiO2, Si, W, and ITO for Sr + Detect and collect the fluorescent photons radiated by [substance], without the need to collect them after being focused by a lens group, which helps to reduce the attenuation of the collected fluorescent photons. Refer to Figure 7 , Figure 7 This is the Sr provided by the embodiment of the present application + Schematic diagram of the radiation laser energy levels, Figure 7 which shows Sr + The energy level transitions at 422 nm, 674 nm, 1092 nm, and 1033 nm, reflecting the Sr + The energy level transitions that occur under laser irradiation at different nanometers. It can be seen that the shorter the wavelength, the higher the energy level.

[0077] However, integrating the single-photon avalanche photodetector 107 near the surface trap has very high requirements for the accuracy of materials and processing technology, making the cost of such detectors relatively high and the usage conditions relatively harsh. In addition, since n+ is 50 μm away from the ion, the size of the single-photon avalanche photodetector 107 is affected by integration, so the size of the single-photon avalanche photodetector 107 is also limited, resulting in the count rate of this type of detector being at the same order of magnitude as that of the PMT, and the collection efficiency of this type of detector for fluorescent photons is also relatively low. It should be noted that since such detectors do not have a lens group for filtering, during the collection of fluorescent photons, they are still affected by the stray light generated by the ion reflecting the detection light, resulting in more background stray light.

[0078] In summary, Figures 3 to 7 For the quantum readout methods shown, there are all situations where the collection efficiency of fluorescent photons is relatively low. Therefore, the embodiment of the present application provides a quantum readout system 200 to replace the conventional lens group to collect photons, avoid being restricted by the structure of the trap electrode and the vacuum environment, increase the solid angle of the collected photons, improve the collection efficiency of photons, and thus improve the readout efficiency of qubit information.

[0079] Refer to Figure 8 , Figure 8This is a structural block diagram of the quantum readout system 200 provided by an embodiment of the present application. The quantum readout system 200 includes a vacuum housing 210, an ion trap 220, a laser device 230, and a detection device 240. The ion trap 220 is disposed within the vacuum housing 210. The ion trap 220 confines ions within the vacuum housing 210 through a confinement electric field. The laser device 230 is disposed outside the vacuum housing 210. The laser device 230 is configured to emit detection light into the vacuum housing 210, and the detection light is used to induce ions to radiate photons. The detection device 240 includes a plurality of detectors 241. The plurality of detectors 241 are arranged along the surface of the vacuum housing 210. The plurality of detectors 241 are used to detect the photons radiated by the ions.

[0080] It can be understood that in Figure 8 , the circles within the ion trap 220 represent ions. The ion trap 220 uses its own confinement electric field to confine the ions within the vacuum housing 210. The laser is irradiated onto the ions within the vacuum housing 210 through the laser device 230, causing the ions to be induced and radiate photons. The plurality of detectors 241 arranged on the surface of the vacuum housing 210 collect the photons radiated by the ions, such that there are detectors 241 around the ions when they radiate photons, so that the solid angle range for the plurality of detectors 241 to collect photons surrounds the ions, thereby expanding the photon collection range, increasing the solid angle of the entire detection device 240 for collecting photons, improving the photon collection efficiency, and thus reducing the impact on the quantum bit information readout efficiency.

[0081] In this embodiment, the quantum readout system 200 further includes a control device 250, and the detection device 240 further includes a data processor 242. As Figure 8 and Figure 9 shown, Figure 8 This is a structural block diagram of the quantum readout system 200 provided by an embodiment of the present application. Figure 9 This is a structural block diagram of the laser device 230 provided by an embodiment of the present application. The data processor 242 is located outside the vacuum housing 210 and is connected to the plurality of detectors 241. The control device 250 is connected to the data processor 242 and the laser device 230. The control device 250 is configured to control the laser device 230 to emit laser light, and is further configured to control the data processor 242 to count the photons collected by the plurality of detectors 241. It can be understood that the data processor 242 is configured to count the photons collected by the plurality of detectors 241 and then send the photon count result back to the control device 250, and the control device 250 obtains the quantum bit information based on the photon count result.

[0082] It should be noted that both the control device 250 and the data processor 242 can be controlled and processed using a Field Programmable Gate Array (FPGA). The purpose is to process the data of multiple detectors 241 through the data processor 242 and reduce the burden on the control device 250. When the control device 250 uses an FPGA, the control device 250 outputs control signals to the laser device 230 and the data processor 242 to control the laser device 230 to emit laser light within a preset period of time and to control the data processor 242 to count the photon signals collected by multiple detectors 241 within a preset period of time. When the data processor 242 uses an FPGA, it mainly collects photon number information and counts the photons to obtain the quantum bit information of the ions.

[0083] Exemplarily, the detector 241 includes an Avalanche Photon Diode (APD). Using the APD instead of a lens group plus a PMT / CCD enables the collection of photons without attenuation caused by the lens group, which can increase the amount of photons collected. The avalanche photodiode collects the photons radiated by the ions and converts the optical signal into an electrical signal, facilitating the transmission of the electrical signal after photon collection to the data processor 242, and further enabling the data processor 242 to count the collected photons based on the electrical signal.

[0084] Since ions, when irradiated by the probing light, not only radiate photons but also reflect some of the probing light, in order to reduce the probing light reflected by the ions collected in the detector 241, the detection device 240 further includes a filter 243 disposed on the collection side of the detector 241, as Figure 8 shown, Figure 8 is the structural block diagram of the quantum readout system 200 provided by the embodiment of the present application, Figure 8 The dashed box in Figure 8 is schematically shown as the filter 243 installed on the collection side of the detector 241. A filter 243 is installed on each detector 241,

[0085] In this embodiment, the shape of the vacuum housing 210 can include any one of a columnar body, a polyhedron, and a spherical body.

[0086] Exemplarily, taking the vacuum housing 210 as a spherical body as an example, a plurality of detectors 241 are arranged around the vacuum housing 210 for at least one week, that is to say, the plurality of detectors 241 are arranged around the vacuum housing 210 for at least one circle. When the plurality of detectors 241 are arranged around the vacuum housing 210 for two or more circles, one circle arranged around the vacuum housing 210 and another circle can be parallel, intersecting or perpendicular to each other. That is to say, the detectors 241 arranged around the vacuum housing 210 for at least one week are equally spaced, so that the plurality of detectors 241 form an array arrangement on the vacuum housing 210. As Figure 8 shown, the detectors 241 in each week arranged around the vacuum housing 210 are equally spaced, that is, the plurality of detectors 241 are evenly distributed along the surface of the vacuum housing 210, so that the plurality of detectors 241 surround the ions in the vacuum housing 210, so as to collect the photons radiated in all directions by the ions, which helps to increase the solid angle of the overall detection device 240 for collecting photons.

[0087] It should be noted that when the plurality of detectors 241 are equally spaced on the surface of the vacuum housing 210, in order to facilitate the detection light emitted by the laser device 230 to irradiate the ions in the vacuum housing 210, there is a gap for the detection light emitted by the laser device 230 to pass through between at least two detectors 241, so that when the detectors 241 are densely arranged on the vacuum housing 210, the laser device 230 can still irradiate the detection light on the ions in the vacuum housing 210.

[0088] In this embodiment, as Figure 9 shown, Figure 9 is a structural block diagram of a plurality of detectors 241 provided in the vacuum housing 210 according to an embodiment of the present application. The laser device 230 includes at least two laser components, and the at least two laser components include a first laser component 231 and a second laser component 232. The first laser component 231 is used to emit a first laser. The second laser component 232 is used to emit a second laser. The first laser and the second laser form the detection light emitted by the laser device 230. The sum of the energy levels of the first laser and the second laser is equal to the energy level required for the ions to induce photons. The frequencies of the first laser and the second laser are both lower than the frequency of the photons.

[0089] Exemplarily, please refer to Figure 9 and Figure 10 , Figure 9 is a structural block diagram of a plurality of detectors 241 provided in the vacuum housing 210 according to an embodiment of the present application. Figure 10Schematic diagram of laser energy level transition for the background fluorescence-free technology provided by the embodiments of the present application. The first laser emitted by the first laser assembly 231 may be a laser with a wavelength of 729 nm in the visible infrared band, and the second laser emitted by the second laser assembly 232 may be a laser with a wavelength of 854 nm in the visible infrared band. The 729-nm laser and the 854-nm laser can be combined into one beam or separately irradiate the ions. However, the 729-nm laser and the 854-nm laser are simultaneously irradiated on the ions, so that the sum of the energy levels formed by the combined irradiation of the 729-nm laser and the 854-nm laser is equal to the energy level required for the ions to induce photons, facilitating the induction of photons from the ions. It should be noted that at this time, the photons radiated by the ions have the same frequency as the photons radiated when the 393-nm laser irradiates the ions. That is to say, the frequency of the photons radiated by the combined irradiation of the 729-nm laser and the 854-nm laser on the ions is greater than the frequency of the 729-nm laser and the frequency of the 854-nm laser. It can be understood that the wavelengths of the 729-nm laser and the 854-nm laser are greater than the wavelength of the photons radiated by the ions. Therefore, when the ions reflect the 729-nm laser and the 854-nm laser, the 729-nm laser and the 854-nm laser with smaller wavelengths can be filtered out by the filter 243, that is, the filter, which helps to achieve background fluorescence-free photon collection. Background fluorescence refers to other light collected by the detector 241 except for photons.

[0090] In this embodiment, the laser assembly includes a laser 2311 and an optical path device 2312. The optical path device 2312 is located on the light-emitting side of the laser 2311, and the optical path device 2312 is used to direct the laser emitted by the laser 2311 towards the vacuum housing 210. It can be understood that each laser assembly can include a laser 2311 and an optical path device 2312. That is to say, the laser 2311 of the first laser assembly 231 emits a 729-nm laser, and the 729-nm laser is irradiated into the vacuum housing 210 through the optical path device 2312 of the first laser assembly 231; the laser 2311 of the second laser assembly 232 emits an 854-nm laser, and the 854-nm laser is irradiated into the vacuum housing 210 through the optical path device 2312 of the second laser assembly 232.

[0091] For the laser 2311, generally, the manipulation laser used in the ion trap 220 requires a narrow linewidth. For example, for the 729-nm laser for manipulating qubits, it is required to be below 100 Hz, and for the 854-nm laser, it is required to be below 1 MHz. To achieve the frequency stability of the laser, it is often necessary to set up an optical path and control the voltage or current of the laser 2311 through an error signal. The error signal can be sent by the control device 250 to lock the laser frequency, or a modulator 2313 can be used to lock the laser power of the laser 2311.

[0092] It should be noted that inFigure 9 In the figure, the first laser assembly 231 and the second laser assembly 232 respectively point to the dotted arrows within the vacuum housing 210, indicating that the lasers of the first laser assembly 231 and the second laser assembly 232 irradiate the ions respectively between two adjacent detectors 241. In Figure 9 the figure, the arrow of the ion, which is shown as a circle, points to the detector 241, indicating that the photons radiated by the ion and the detected light reflected are directed towards the detector 241. After Figure 9 the dotted box shown as a filter in the figure filters out the emitted detected light, which helps to improve the purity of the photons collected by the detector 241.

[0093] In this embodiment, the laser device 230 further includes a modulation module 233, and the modulation module 233 is connected to the control device 250. The modulation module 233 includes a radio frequency source 2331 and a radio frequency switch 2332. The radio frequency switch 2332 is connected between the radio frequency source 2331 and the optical path device 2312. The radio frequency switch 2332 is used to control the on / off of the radio frequency signal between the radio frequency source 2331 and the optical path device 2312. The optical path device 2312 is configured to conduct after receiving the radio frequency signal.

[0094] In Figure 9 the figure, it can be seen that the control device 250 is connected to the modulation module 233 and also to the data processor 242. Specifically, the radio frequency switch 2332 is connected to the control device 250 so that the control device 250 can control the radio frequency switch 2332 to open within a preset time, and then the radio frequency switch 2332 closes after the preset time ends. In this way, the radio frequency signal generated by the radio frequency source 2331 is sent to the optical path device 2312 during the time when the radio frequency switch 2332 is open. During the time when the optical path device 2312 receives the radio frequency signal, the optical path for the laser to be emitted into the channel within the vacuum housing 210 is opened. Eventually, during the time when the radio frequency switch 2332 is open, the laser irradiates the ions within the vacuum housing 210 and induces the ions to radiate photons, so that the detector 241 can collect the photons radiated by the ions during the time when the radio frequency switch 2332 is open.

[0095] It can be understood that the radio frequency switch 2332 can change the opening duration of the optical path, and thus change the duration of the detected light irradiating the ions. That is to say, when the control device 250 controls the radio frequency switch 2332 to open within a preset time, the control device 250 also controls the data processor 242 to start counting the photons collected by the detector 241, and the duration for which the data processor 242 starts counting is the same as the time when the radio frequency switch 2332 is open. Until the radio frequency switch 2332 closes and the ions no longer radiate photons, at this time the data processor 242 also stops counting the photons collected by the detector 241.

[0096] In this embodiment, the optical path device 2312 includes an optical path and a modulator 2313. The optical path is for the probe light to pass through. The modulator 2313 is disposed on the optical path. The modulator 2313 is connected to the RF switch 2332. The modulator 2313 is used to control the conduction of the optical path after receiving an RF signal. It can be understood that when the RF source 2331 generates an RF signal, the RF signal is conducted to the modulator 2313 through the RF switch 2332, and after the modulator 2313 receives the RF signal, the optical path is conducted, so that the laser can irradiate into the vacuum housing 210 through the optical path, enabling the RF switch 2332 to control the conduction duration of the optical path through the modulator 2313. Moreover, since the laser irradiates into the vacuum housing 210 through the optical path, the direction of the laser entering the vacuum housing 210 can be changed through the optical path, so as to facilitate adjusting the direction and angle of the laser irradiating into the vacuum housing 210.

[0097] In this embodiment, there are cases where multiple detectors 241 are arranged along the inner surface and the outer surface of the vacuum housing 210. Therefore, the positions of the multiple detectors 241 provided on the vacuum housing 210 will be further described below in conjunction with some embodiments.

[0098] Embodiment 1:

[0099] Refer to Figure 9 , Figure 9 which is a structural block diagram of multiple detectors 241 provided in the embodiment of the present application arranged in the vacuum housing 210. Figure 9 The multiple detectors 241 in it include multiple first detectors. The multiple first detectors are located inside the vacuum housing 210 and are arranged along the inner surface of the vacuum housing 210, and the material of the vacuum housing 210 is metal. There are openings for optical and electrical connections left on the metal vacuum housing 210, and the openings are connected by flanges to maintain the vacuum environment inside the vacuum housing 210. The optical connection of the metal vacuum housing 210 means that an optical fiber passes through the flange interface and is connected to the inside of the vacuum housing 210, and the laser enters the vacuum housing 210 from between adjacent detectors 241. The electrical connection of the metal vacuum housing 210 means that multiple detectors 241 are connected to the data processor 242 through wire lines, so that each detector 241 can be connected to the data processor 242, facilitating the data processor 242 to count the number of photons collected by the multiple detectors 241.

[0100] Next, a simplified model will be introduced to calculate the number of detectors 241 that can be arranged on the vacuum housing 210 and the solid angle. The calculation results have little error from the actual results. Refer to Figure 11 , Figure 11 which is a schematic diagram of the solid angle of the detector 241 provided in the embodiment of the present application. Each detector 241 is placed at a distance of 10 cm from the ion, as Figure 11a in it. Assume that the solid angle for each detector 241 to collect photons is a circular surface with a radius of 0.5 cm, as shown in Figure 11 b in it, then the angle that the detector 241 opens to the ion:

[0101]

[0102] It can be seen from this that the smaller a is, the larger the solid angle that the detector 241 opens to the ion; the larger a is, the smaller the solid angle that the detector 241 opens to the ion.

[0103] For this reason, assume how many detectors 241 need to be placed at the same 10 cm distance in the blade trap. Refer to Figure 12 , Figure 12 is the axial schematic diagram of the layout of the blade trap detector 241 provided by the embodiment of the present application. Laser can be passed in the horizontal plane. Figure 12 The direction of the arrow in it is the laser direction. The crossed electrodes form an included angle typical value of 120°. The included angle typical value refers to the angle size between two adjacent electrodes in the case of large electrode crossing. The crossed electrodes confine the ions, and since the crossed electrodes will block the laser reflected by the ions, a plurality of detectors 241 arranged within this included angle typical value of 120° can collect the photons radiated by the ions. However, this is actually the arrangement of a plurality of detectors 241 at an included angle typical value of 120° when the vacuum housing 210 is in a columnar shape. In the columnar vacuum housing, due to the different distances between the circumferential surface and the two end faces of the columnar body from the ions, the distribution positions vary greatly, which is difficult for the arrangement and collection of the detectors 24l. If the two end faces of the columnar vacuum housing 210 are abandoned, it can be understood that a spherical body is intercepted within the columnar vacuum housing 210, and then within the spherical vacuum housing 210, the number of detectors 241 that can be arranged at an included angle typical value of 120° and the solid angle are solved. Although the number of detectors 241 arranged is reduced compared to the case of the columnar shape when the vacuum housing 210 is in a spherical shape, under the spherical vacuum housing 210, the installation, photon collection, photon counting, etc. of the detectors 241 are more convenient, which conforms to the common symmetry of the metal vacuum housing 210.

[0104] In order to calculate how many detectors 241 can be arranged on the spherical vacuum housing 210 and the solid angle of the detectors 241, and calculate the photon collection efficiency of the detectors 241 according to the number of detectors 241, refer to Figure 13 , Figure 13Schematic diagram of 955 points for spherical tiling provided by an embodiment of the present application. Points can be evenly distributed on the spherical surface with a radius of 10 cm, and the spacing between points is approximately 1 cm. Using the Fibonacci grid algorithm, through numerical simulation, it can be obtained that when taking 955 points, 218 detectors 241 can be placed within an angular typical value of 120° (points less than 1 cm away from the boundary have been excluded).

[0105] Thus, the total solid angle of ions for these 218 detectors 241:

[0106] Ω = 218 * 2π(1 - cos(arctan(0.5 / 10))) ≈ 0.1360 * 4π;

[0107] That is to say, the photons detected in this part account for 13.6% of the total number of photons. Considering that detectors 241 can be placed on both sides of the angular typical value of 120°, the collection ratio can reach 27.2%. If the detectors 241 have a quantum efficiency of 30% and the filter transmittance is 90%, then the total collection efficiency:

[0108]

[0109]

[0110] It can be seen from this that in the case where the vacuum housing 210 is spherical and the angular typical value is 120°, the collection efficiency of photons by arranging 218 detectors 241 is 2.8 times that of the traditional lens group method, and the detectors 241 are arranged along the surface of the spherical vacuum housing 210, which can increase the solid angle range from <10% to ~80%.

[0111] Embodiment 2:

[0112] Refer to Figure 14 , [[ID=�7]] Figure Structural block diagram of multiple detectors 241 provided by an embodiment of the present application and arranged outside the vacuum housing 210. The difference between this embodiment and Embodiment 1 is that the multiple detectors 241 include multiple second detectors, which are located outside the vacuum housing 210 and arranged along the outer surface of the vacuum housing 210, and the material of the vacuum housing 210 is glass. Using glass instead of a metal vacuum housing 210 can increase the light transmittance of the vacuum housing 210, and since the detectors 241 are located outside the vacuum housing 210, the number of flange interfaces on the vacuum housing 210 is reduced, increasing the light transmission range of the vacuum housing 210 and further increasing the photon collection range of the detectors 241. Moreover, when the detectors 241 are evenly arranged along the outer wall of the vacuum housing 210, transferring the installation and connection of the detectors 241 outside the vacuum housing 210 helps to reduce the installation and connection difficulty of the detectors 241.

[0113] That is to say, multiple detectors 241 are located outside the vacuum housing 210 and connected to the data processor 242, which reduces the installation difficulty of the detectors 241. Moreover, there is a gap between adjacent detectors 241 for the laser beam exported by the optical path device 2312 to pass through. Therefore, it should be noted that, except for the different installation positions of the detectors 241, other settings in this embodiment are the same as those in the first embodiment.

[0114] The embodiment of the present application also provides a quantum readout method for the readout method of the quantum readout system 200 to facilitate the readout of qubit information. Refer to ​ , ​ which is the flowchart of the quantum readout method provided by the embodiment of the present application. This readout method includes S201 to S205:

[0115] S201. Cooling and initial state preparation.

[0116] For the ions confined in the vacuum housing 210, the cooling light emitted by the laser device 230 is used for cooling, and the pumping light emitted is used to initialize the ion quantum state, so that the internal quantum state of the cooled ions is initialized, and the initial state preparation of the ions is completed.

[0117] S202. Obtaining the quantum state.

[0118] The manipulation light emitted by the laser device 230 interacts with the ions to obtain a specific quantum state of the ions, and the quantum state of the ions is stabilized.

[0119] S203. Turning on and off the detection light.

[0120] The control device 250 controls the laser device 230 to emit the detection light within a preset time, so that the detection light irradiates the ions, inducing the ions to radiate photons within this preset time. After the preset time ends, the laser device 230 stops emitting the detection light, and the detector 241 collects the photons within this preset time.

[0121] S204. Counting by the data processor 242.

[0122] While the control device 250 controls the laser device 230 to emit the detection light within a preset time, it also controls the data processor 242 to count the number of photons collected by the detector 241 within this preset time. It can be understood that the duration of the detection light emitted by the laser device 230, the working time of the data processor 242, and the duration of the photons collected by the detector 241 are the same.

[0123] S205. Obtaining the photon counting result.

[0124] The data processor 242 counts the photon counting result and feeds back the qubit information according to the photon counting result.

[0125] It should be noted that the control device 250 controls the laser device 230 and the data processor 242 to work in the same time sequence. That is to say, steps S203 and S204 are carried out in the same time sequence, so that the data processor 242 can read and count the number of photons collected by the detector 241 in the same time sequence. After that, the collection of photons can be started again between steps S201 and S202.

[0126] As described above, it is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A quantum readout system, characterized in that, Comprising: A vacuum housing; An ion trap disposed within the vacuum housing, the ion trap being configured to confine ions within the vacuum housing; A laser device disposed outside the vacuum housing, the laser device being configured to emit probe light into the vacuum housing, the probe light being configured to induce the ions to radiate photons; A detection device comprising a plurality of detectors arranged along the surface of the vacuum housing, the plurality of detectors being configured to collect the photons radiated by the ions.

2. The quantum readout system according to claim 1, characterized in that, The plurality of detectors include a plurality of first detectors located inside the vacuum housing and arranged along the inner surface of the vacuum housing.

3. The quantum readout system according to claim 1 or 2, characterized in that, The plurality of detectors include a plurality of second detectors located outside the vacuum housing and arranged along the outer surface of the vacuum housing.

4. The quantum readout system according to any one of claims 1-3, characterized in that, The plurality of detectors are arranged around the vacuum housing for at least one full turn.

5. The quantum readout system according to claim 4, wherein The detectors arranged around the vacuum housing for at least one full turn are equally spaced.

6. The quantum readout system according to any one of claims 1-5, characterized in that, Between at least two of the detectors, there is a gap for the probe light emitted by the laser device to pass through.

7. The quantum readout system according to any one of claims 1-6, characterized in that, The shape of the vacuum housing includes any one of a columnar body, a polyhedron, and a spherical body.

8. The quantum readout system according to any one of claims 1-7, characterized in that, The detection device further includes a filter disposed on the collection side of the detectors, the filter being configured to filter out the probe light reflected by the ions.

9. The quantum readout system according to any one of claims 1-8, characterized in that, The laser device includes at least two laser assemblies, the at least two laser assemblies including a first laser assembly and a second laser assembly, the first laser assembly being configured to emit first laser light, and the second laser assembly being configured to emit second laser light; the first laser light and the second laser light together form the probe light emitted by the laser device; the sum of the energy levels of the first laser light and the second laser light is equal to the energy level required for the ions to induce the photons, and the frequencies of the first laser light and the second laser light are both lower than the frequency of the photons.

10. The quantum readout system according to claim 9, wherein The laser assembly includes a laser and an optical path device, the optical path device being located on the light-emitting side of the laser, and the optical path device being configured to direct the laser light emitted by the laser towards the vacuum housing.

11. The quantum readout system according to claim 10, wherein The laser device further includes a radio frequency source and a radio frequency switch connected between the radio frequency source and the optical path device, the radio frequency switch being configured to control the on / off of the radio frequency signal between the radio frequency source and the optical path device, and the optical path device being configured to conduct upon receiving the radio frequency signal.

12. The quantum readout system according to claim 11, wherein The optical path device includes an optical path and a modulator, the optical path for the probe light to pass through, the modulator being disposed on the optical path and connected to the radio frequency switch, the modulator being configured to control the optical path to conduct upon receiving the radio frequency signal.

13. The quantum readout system according to any one of claims 1-12, wherein The detection device further includes a data processor connected to the plurality of detectors; The quantum readout system further includes a control device connected to the data processor and the laser device, the control device being configured to control the laser device to emit laser light, and the control device being configured to control the data processor to count the photons collected by the plurality of detectors.

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