Quantum bit detection module and quantum bit control system

Abstract

This quantum bit detection module comprises: an imaging unit that captures an image of an imaging region including a position where a quantum bit is placed, and generates first image data corresponding to the imaging region; a processing unit that sets a region of interest smaller than the imaging region and including the position where the quantum bit is placed, and cuts out second image data corresponding to the set region of interest from the first image data; and an output unit that externally outputs output data including the second image data.

Description

Quantum bit detection module and quantum bit control system

[0001] The present disclosure relates to qubit detection modules and qubit control systems.

[0002] Quantum computing technology utilizes the properties of quantum superposition to construct quantum bits. Generally, controlling the quantum superposition state requires advanced technology, and the quantum superposition state is known to be very unstable. Therefore, error correction of quantum bits is important in quantum computing.

[0003] Dolev Bluvstein, Harry Levine, Giulia Semeghini, Tout T. Wang, Sepehr Ebadi, Marcin Kalinowski, Alexander Keesling, Nishad Maskara, Hannes Pichler, Markus Greiner, Vladan Vuletic & Mikhail D. Lukin, “A quantum processor based on coherent transport of entangled atom arrays,” Nature, Vol.604, pp.451-471, 2022.

[0004] For example, in a technique for detecting the state of a quantum bit and feedback-controlling the state of the quantum bit in accordance with the detection result, there is a demand for faster detection of the quantum bit state in order to perform feedback control at high speed.

[0005] An object of one aspect of the present disclosure is to provide a quantum bit detection module and a quantum bit control system that can speed up quantum bit detection.

[0006] One aspect of the quantum bit detection module includes an imaging unit that images an imaging area including the placement position of the quantum bit and generates first image data corresponding to the imaging area, a processing unit that sets a region of interest that is smaller than the imaging area and includes the placement position of the quantum bit, and cuts out second image data from the first image data that corresponds to the set region of interest, and an output unit that outputs output data including the second image data to the outside.

[0007] In the quantum bit detection module described above, output data including second image data indicating the quantum bit state is output to the outside of the module. The second image data corresponds to a region of interest that is smaller than the imaging region of the imaging unit, and therefore has a smaller data volume than the first image data corresponding to the imaging region. This reduces the amount of data output to the outside of the module, allowing data about the quantum bit to be output at high speed. In other words, quantum bit state detection can be accelerated.

[0008] In one example, the processing unit may acquire third image data in which multiple pieces of second image data corresponding to multiple regions of interest are combined with each other. In this configuration, it is not necessary to include additional information such as address data corresponding to the regions of interest in the output data.

[0009] In one example, the processing unit may combine the second image data with each other so as to maintain the order of arrangement of the regions of interest in the imaging area. In this configuration, the third image data is acquired by combining the second image data in the original order. For example, when a user visually checks the third image data, the user can easily understand the state of each region of interest.

[0010] In one example, the processing unit may extract multiple pieces of second image data corresponding to multiple regions of interest from the first image data, and the output unit may sequentially output each of the extracted multiple pieces of second image data. In this configuration, data can be output for each region of interest, so that quantum bit information can be output without delay.

[0011] In one example, the processing unit may set the region of interest to include the locations of multiple quantum bits, which reduces the number of times the region of interest needs to be cut out.

[0012] In one example, the processor may adjust the size of the region of interest depending on the position of the region of interest within the imaging region. In this configuration, image distortion in the first image data can be corrected.

[0013] A quantum bit control system according to one aspect includes a quantum bit controller that controls a quantum bit based on output data including second image data output from the quantum bit detection module.

[0014] In one example, the quantum bit control unit controls the quantum bit based on position information of the region of interest acquired separately from the output data including the second image data, i.e., the quantum bit control unit identifies the position of the quantum bit in the output data based on the separately acquired position information of the region of interest.

[0015] According to one aspect of the quantum bit detection module and quantum bit control system, quantum bit state detection can be speeded up.

[0016] Fig. 1 is a diagram showing the configuration of a quantum bit control system according to one embodiment. Fig. 2 is a diagram showing a histogram of integrated brightness values ​​created based on a simulation. Fig. 3 is a diagram schematically showing an image captured by a quantum bit detection module. Fig. 4 is a schematic diagram visually explaining one example of processing in a processing unit. Fig. 5 is a schematic diagram visually explaining another example of processing in a processing unit. Fig. 6 is a schematic diagram visually explaining yet another example of processing in a processing unit.

[0017] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. For convenience, substantially identical elements will be denoted by the same reference numerals, and their description may be omitted.

[0018] 1 is a diagram showing a schematic configuration of a quantum bit control system. The quantum bit control system 1 according to this embodiment is a system for controlling the state of a quantum bit that can be in a quantum superposition state. The quantum bit control system 1 can be used, for example, in quantum computer technology that uses neutral atoms trapped by optical tweezers or the like as quantum bits.

[0019] An example processing sequence of quantum computer technology may include a preparation stage in which a quantum processing unit (QPU) traps atoms in a vacuum and arranges the trapped atoms at predetermined positions to form quantum bits, and an operation stage in which quantum bit initialization and quantum calculation are repeated. The quantum bit control system 1 can acquire the respective states of the trapped quantum bits, the rearranged quantum bits, and the quantum bits after quantum calculation. For example, in the operation stage, the quantum bit control system repeats quantum bit initialization and quantum calculation while performing error correction feedback processing based on the acquired quantum bit states.

[0020] In this embodiment, a quantum bit composed of neutral atoms has at least two different energy levels (internal states). One example of a quantum bit may have at least |↓>, a lower energy level; |↑>, an energy level higher than |↓>; and |e'>, an energy level different from |↑> that excites |↓> and emits fluorescence. For example, a quantum bit can be in a superposition state of |↓> and |↑>. When the quantum bit is in |↓>, if light resonating between |↓> and |e'> strikes it, it absorbs the light, transitions to |e'>, emits fluorescence, and returns to |↓>. Even if the same light is irradiated when the quantum bit is in |↑>, the quantum bit does not transition to |e'>, and no fluorescence is observed. Hereinafter, |↓> may be referred to as the ground level, |↑> as the excited level, and |e'> as the fluorescence level. Light resonating between the ground level and the fluorescence level may be referred to as resonant light.

[0021] As shown in FIG. 1 , an example quantum bit control system 1 includes at least a quantum bit detection module 3, a quantum bit control unit 30, and a module control unit 40. The quantum bit detection module 3 is a device for detecting the state of a quantum bit. In this embodiment, the quantum bit detection module 3 detects the state of the quantum bit by detecting photons emitted from the quantum bit. For example, the photons emitted from the quantum bit may be fluorescence of the quantum bit. In one example, the quantum bit detection module 3 may be an imaging device with low readout noise that allows the number of photoelectrons to be identified.

[0022] The quantum bit detection module 3 includes an imaging unit 10, a processing unit 20, and an output unit 25. The imaging unit 10, the processing unit 20, and the output unit 25 may be housed in a housing 5 that forms the exterior of the module. The imaging unit 10 captures an image of an object and generates image data. Note that capturing an image of the object may mean converting the image of the object into an electrical signal. The imaging unit 10 may be a so-called image sensor, and in one example, may be a CMOS (Complementary Metal-Oxide-Semiconductor) image sensor. The imaging unit 10 may also be a CCD (Charge Coupled Device) image sensor. The imaging unit 10 may also be a SPAD (Single-Photon Avalanche Diode) image sensor.

[0023] The imaging unit 10 includes a plurality of pixels 11 and an A / D converter 15. The plurality of pixels 11 are arranged two-dimensionally in rows and columns. Each pixel 11 includes a photodiode (photoelectric conversion element) 12 and an amplifier 13. The photodiode 12 accumulates electrons (photoelectrons) generated by input photons as electric charges. The amplifier 13 converts the electric charges accumulated in the photodiode 12 into voltages and amplifies them. The amplified voltages are transferred to vertical signal lines 16 for each line (each row) by switching the selection switches 14 of each pixel 11. Each vertical signal line 16 includes a CDS (Correlated Double Sampling) circuit 17. The CDS circuit 17 removes noise that varies between pixels and temporarily stores the transferred voltages.

[0024] The A / D converter 15 converts the voltages output from the amplifiers 13 in each of the multiple pixels 11 into digital values. Because the digital values ​​reflect the luminance of the pixel 11, the digital values ​​may be referred to as luminance values ​​in the following description. Note that the luminance values ​​may be synonymous with pixel values. In this embodiment, the A / D converter 15 converts the voltages stored in the CDS circuit 17 into digital values. The converted digital values ​​are output to the processing unit 20. For example, the digital values ​​may be sent to a horizontal signal line (not shown) by switching column selection and output to the processing unit 20. In this way, when photons are input to each pixel 11, the imaging unit 10 outputs a digital value corresponding to the number of input photons to the processing unit 20. Note that the A / D converter 15 may be provided in each pixel 11.

[0025] When the voltage amplified by the amplifier 13 is read out, random read noise is generated within the amplifier 13. If the read noise is large, the accuracy of detecting the state of the quantum bit may decrease. For example, when detecting whether or not a quantum bit is emitting fluorescence, the read noise of the amplifier 13 may increase the digital value, leading to the possibility that it may be determined that fluorescence is being emitted from the quantum bit even though there is no fluorescence from the quantum bit.

[0026] In quantum computing technology, it is expected that quantum bit state detection will be performed repeatedly, and therefore, it is desirable for the accuracy of state detection in a single run to be close to 100%. Therefore, in this embodiment, an imaging unit 10 with low readout noise can be used so that the accuracy of state detection in a single run is 99.9% or higher. For example, the performance of the imaging unit 10 can be evaluated based on image simulations of quantum bits that emit fluorescence and quantum bits that do not emit fluorescence. In one example simulation, the luminance integrated value of a predetermined area (e.g., 6 × 6 pixels) containing the quantum bits is calculated for each of the quantum bits that emit fluorescence and the quantum bits that do not emit fluorescence, and a histogram of the luminance integrated value is created. Then, based on the histogram, a threshold value for distinguishing between the quantum bits that emit fluorescence and the quantum bits that do not emit fluorescence is set, and the luminance integrated value of each quantum bit is determined based on the threshold value.

[0027] FIG. 2 shows the results of a simulation in which the readout noise of the imaging unit 10 is 0.27 e-rms. FIG. 2 is a histogram in which the horizontal axis represents the integrated brightness value of the quantum bit, and the vertical axis represents the frequency of quantum bits with fluorescence and quantum bits without fluorescence. In this example, the exposure time is 20 ms. In the simulation example shown in FIG. 2, the accuracy of distinguishing between quantum bits with fluorescence and quantum bits without fluorescence was 99.98%. Similar simulations using different readout noises showed that when the readout noise was approximately 0.7 e-rms or less, the discrimination accuracy was 99.9% or more. In this embodiment, with the aim of setting the discrimination accuracy to 99.9% or more, a CMOS image sensor with a readout noise of approximately 0.7 e-rms or less is used as the imaging unit 10.

[0028] The imaging unit 10 images an imaging region including the arrangement positions of the quantum bits, and generates image data (first image data) corresponding to the imaging region. The imaging region may have a size that allows simultaneous imaging of all quantum bits constructed in the QPU. The image data may be composed of a plurality of pixel data. The plurality of pixel data may be composed of identification data that identifies each pixel 11 and data indicating a brightness value associated with each identification data. An example of the pixel data may be data in which position data (e.g., coordinate data, address, etc.) indicating the position of a pixel is associated with the brightness value of the pixel. Note that, in this embodiment, imaging of the imaging region by the imaging unit 10 may be performed in a state in which each quantum bit is irradiated with resonant light.

[0029] The imaging unit 10 sequentially generates each pixel data constituting a plurality of pixel data and sequentially outputs the generated pixel data to the processing unit 20. For example, in the imaging unit 10, the luminance value of each pixel 11 is sequentially output from the A / D converter 15, and the output luminance value is input to the processing unit 20 together with position data specifying the position of the pixel 11. The order in which the luminance values ​​are output may be determined in advance. Note that the imaging unit 10 may continuously capture an imaging area to be imaged over multiple frames. In this case, the imaging unit 10 sequentially outputs pixel data of each pixel to the processing unit 20 for each frame.

[0030] The processing unit 20 generates information that can determine the state of the quantum bit based on the image data. An example of the processing unit 20 may include one or more field-programmable gate arrays (FPGAs). An FPGA is an integrated circuit that can program circuit configurations, such as an array of logic gates, and can quickly execute predetermined calculations (functions) according to a program. The calculation circuit that constitutes the processing unit 20 is not limited to an FPGA, but may also be configured using an application specific integrated circuit (ASIC), a microcomputer, or the like. In this embodiment, since the processing unit 20 is configured using an FPGA, processing time can be reduced compared to when the processing unit is configured using a CPU, etc.

[0031] As shown in Fig. 1, the processing unit 20 has, as its functional units, a region of interest (ROI) setting unit 21 and an image cropping unit 23. The ROI setting unit 21 sets, within the imaging area, a plurality of ROIs that are smaller than the imaging area. Fig. 3 is a diagram schematically showing an image captured by the quantum bit detection module 3. Fig. 4 is a schematic diagram visually explaining the processing in the processing unit.

[0032] In the image data 100a shown in Figures 3 and 4, the quantum bits 105 that emitted fluorescence when captured are shown in black, and the background is shown in white. The position and state of the quantum bits 105 are controlled by the quantum bit control unit 30. The quantum bits 105 are placed at predetermined positions using, for example, an atom trapping technique such as optical tweezers. Note that other known techniques may be used to place the quantum bits 105 at predetermined positions in space.

[0033] In the example of the imaging region 100 shown in FIGS. 3 and 4 , atoms forming the quantum bits 105 are arranged at positions spaced apart from each other in an 8×8 grid. In the following description, the vertical direction (height direction) when viewed from the front of the drawing may be referred to as the X direction, and the horizontal direction as the Y direction. As shown in the left diagram of FIG. 4 , the ROI setting unit 21 sets multiple ROIs 101 corresponding to the multiple quantum bits 105 within the imaging region 100. In FIG. 4 , the set ROIs 101 are indicated by dashed lines. As shown in the diagram, the ROIs 101 in the example surround each quantum bit 105 in a rectangular shape. The size of the ROI 101 may be any size that can surround the quantum bits 105. For example, if the quantum bits 105 have a size corresponding to approximately 1×1 to 4×4 pixels, the ROI 101 may be composed of approximately 1×1 to 6×6 pixels. It should be noted that the number of pixels corresponding to the quantum bits 105 and the ROI 101 is merely an example and is not limited to this.

[0034] 4, the image cropping unit 23 acquires ROI image data 101a (second image data) from the image data 100a. The ROI image data 101a is acquired by cropping an area corresponding to the set ROI 101 from the image data 100a. That is, the image cropping unit 23 crops the ROI image data 101a for each ROI 101 set by the ROI setting unit 21 from the image data 100a generated by the imaging unit 10. In one example, the ROI image data 101a may be left in the image data 100a generated by the imaging unit 10, and portions other than the ROI image data 101a may be removed.

[0035] The image cropping unit 23 generates one composite image data 110 (third image data) by combining the ROI image data 101a corresponding to the multiple ROIs 101 cropped for each frame (see the right diagram in FIG. 4 ). The image cropping unit 23 generates the composite image data 110 so that the arrangement order of the set ROIs 101 is maintained. For example, in FIG. 4 , the ROI image data 101a of the ROI 101 arranged in the upper right corner of the imaging area 100 constitutes the area in the upper right corner of the composite image data 110. The image cropping unit 23 sends the composite image data 110 to the output unit 25.

[0036] The output unit 25 outputs composite image data 110, which is output data including the ROI image data 101a, to the outside of the quantum bit detection module 3. The output unit 25 of this embodiment outputs the composite image data 110 to the quantum bit control unit 30. Data transmission by the output unit 25 may be performed by any type of protocol, such as Cameralink, CoaXPress, GigE Vision, Universal Serial Bus (e.g., USB 3.0, USB 3.1, etc.), Peripheral Component Interconnect Express (PCIe), etc. An example of the output unit 25 may be an interface compatible with the Cameralink standard.

[0037] The processing unit 20 may perform filtering on the image data captured by the imaging unit 10. Examples of filtering include threshold processing (static or dynamic), Gaussian fitting, pattern matching, and Fourier transform. The filtering may also be processing based on machine learning. Filtering the image data can improve the accuracy of determining the state of the quantum bit. The filtering may be performed for each ROI 101, or may be performed on the entire image data 100a.

[0038] The quantum bit control unit 30 controls the state of the quantum bit 105 based on the data input from the quantum bit detection module 3. The quantum bit control unit 30 may include a processing circuit to which the data from the quantum bit detection module 3 is input, and a laser irradiation system controlled by the processing circuit. The laser irradiation system may be configured as a device separate from the quantum bit control unit 30. For example, the processing circuit of the quantum bit control unit 30 may be configured to include an FPGA.

[0039] The quantum bit control unit 30 detects the state of the quantum bit 105 based on the composite image data. For example, the quantum bit control unit 30 identifies an area in the composite image data 110 corresponding to each ROI 101. That is, it identifies each ROI image data 101a constituting the composite image data 110. In one example, the quantum bit control unit 30 may identify each ROI image data 101a based on position information of the ROI 101 acquired in advance. The position information of the ROI 101 may be address data assigned to the ROI 101, and may be input from the module control unit 40 to the quantum bit control unit 30. For example, if the size of each ROI 101 is set uniformly, the order of each ROI 101 in the X and Y directions may be identified from the address data, thereby identifying each ROI image data 101a.

[0040] The quantum bit control unit 30 calculates state information of the quantum bits 105 in the ROI 101 for each of the identified ROI image data 101a. In one example, the state information may be binary data indicating the state of the quantum bit. For example, the quantum bit control unit 30 may have a brightness value threshold for determining the state of the quantum bit. The quantum bit control unit 30 may obtain the state information by comparing the threshold with the brightness value in the ROI.

[0041] This threshold may be determined based on prior experiments or the like using a method similar to that used for the threshold in the simulation described above. That is, the luminance integrated value within ROI 101 is calculated, and a threshold for distinguishing between quantum bits 105 that emit fluorescence and quantum bits 105 that do not emit fluorescence is derived from a histogram created based on the luminance integrated value. Quantum bits 105 that emit fluorescence are quantum bits whose internal state is in the ground level and emit fluorescence when irradiated with light that transitions to the fluorescence level. Quantum bits 105 that do not emit fluorescence are quantum bits whose internal state is in the excited level.

[0042] The quantum bit control unit 30 may calculate an integrated brightness value by accumulating the brightness values ​​of all pixels in the ROI image data 101a to be determined, and based on a comparison between this integrated brightness value and a threshold, determine that the quantum bit 105 is in the ground state if the integrated brightness value is greater than the threshold, and determine that the quantum bit 105 is in the excited state if the integrated brightness value is equal to or less than the threshold. The quantum bit control unit 30 may associate the determination result with identification data for the ROI 101. The determination result may be binary data indicating the presence or absence of fluorescence, i.e., binary data indicating the ground state or the excited state. The identification data for the ROI 101 may be address data assigned to each ROI 101, or may be position data of a reference pixel within each ROI 101. The reference pixel may be a predetermined pixel (e.g., the pixel in the upper left corner) within each ROI 101 in the image data 100a, or may be a pixel located at the center of the quantum bit 105 in each ROI 101.

[0043] When image data over multiple frames is output from the processing unit 20 to the quantum bit control unit 30, the quantum bit control unit 30 may calculate the state information for each frame of the image data. That is, the integrated value of the luminance values ​​of the pixels in the ROI 101 may be an integrated value for one frame, rather than an integrated value over multiple frames.

[0044] The quantum bit control unit 30 has correct information about the state that the quantum bit should be in, and compares this correct information with the quantum bit state information acquired based on the composite image data 110. If the comparison between the correct information and the state information identifies a quantum bit that is not in the correct state, the quantum bit control unit 30 corrects the state of that quantum bit. The correction of the quantum bit state can be performed by controlling the state of laser irradiation on the quantum bit.

[0045] For example, if a quantum bit that should be at an excited state is at the ground state and emitting fluorescence, the quantum bit control unit 30 may irradiate the quantum bit with a laser to bring it to the excited state. Thus, error correction (state control) using laser irradiation may be a technique for manipulating a quantum state by irradiating a specific quantum bit with a laser. Furthermore, the error correction technique may be a technique for manipulating the arrangement of quantum bits by controlling the intensity, phase, etc. of a laser irradiated onto the quantum bit using a spatial light modulator (SLM), an acousto-optical modulator (AOM), or the like. Note that, for example, assuming that all quantum bits 105 are controlled to the ground state, if there is an ROI 101 in which no fluorescence is detected, the quantum bit control unit 30 may determine that the quantum bit in that ROI 101 is not trapped in the position where it should be. In this case, the quantum bit control unit 30 may rearrange the quantum bits using optical trap control using a laser.

[0046] The module control unit 40 controls the operation of the quantum bit detection module 3. The module control unit 40 is physically configured to include storage devices such as RAM and ROM, a processor (arithmetic circuit) such as a CPU, a communication interface, etc. Examples of the module control unit 40 include a personal computer, a cloud server, a smart device (smartphone, tablet terminal, etc.), a microcomputer, and an FPGA. A display device such as a display, and an input device such as a keyboard and a mouse can be connected to the module control unit 40.

[0047] The module control unit 40 is communicatively connected to the processing unit 20 via an output terminal different from the output unit 25 provided in the quantum bit detection module 3. The module control unit 40 is also communicatively connected to the quantum bit control unit 30. The module control unit 40 may acquire image data 100a from the processing unit 20 and display an image of the imaging region 100 on a display. In one example, the module control unit 40 may be used to control the setting of the ROI 101. For example, a user may specify an ROI by operating a mouse while the image data 100a of the imaging region 100 is displayed on the display. As one example, when the mouse is dragged on the display, the module control unit 40 may recognize a rectangular frame having a diagonal line connecting the start point and end point of the drag as the ROI. Furthermore, when the mouse is clicked on the display, the module control unit 40 may recognize the clicked coordinates as the center pixel of the ROI and recognize certain surrounding pixels including the center pixel as the ROI.

[0048] Furthermore, module control unit 40 may automatically recognize image data 100a in which quantum bits 105 are captured, thereby determining the setting positions of quantum bits 105 within imaging region 100. In this case, module control unit 40 may form a grid with intersections at the positions of the recognized quantum bits 105, and form an ROI with the intersections of the grid as its center.

[0049] The user may also specify an ROI by inputting position data (coordinate data) of the ROI. The position data may be numerical data input directly by the user or an external table-format file. The position data may be composed of coordinates of a predetermined reference point of the ROI, data determining the vertical width of the ROI, and data determining the horizontal width of the ROI. The coordinates of the reference point may be composed of an offset distance (offset X) from the upper left corner of the imaging area to the right (horizontal direction) and an offset distance (offset Y) from the upper left corner of the image to the bottom (vertical direction). The position data may also be the coordinates of two diagonal points of a rectangular ROI. In the mode in which position data is input, image data of the imaging area does not need to be displayed on the display.

[0050] The data specified by the user may also be the position data of a specific ROI, the step and number in the X direction, and the step and number in the Y direction. In this case, all ROIs will be formed with the same size. Similarly, when forming ROIs with the same size, the reference coordinates of each ROI (e.g., the coordinates of the upper left corner) and the vertical and horizontal distances common to all ROIs may be specified.

[0051] As described above, the example quantum bit detection module 3 includes an imaging unit 10 that images an imaging area 100 including the placement position of the quantum bit 105 and generates image data 100a (first image data) corresponding to the imaging area 100, a processing unit 20 that sets an ROI 101 including the placement position of the quantum bit 105 and cuts out ROI image data 101a (second image data) corresponding to the set ROI 101 from the image data 100a, and an output unit 25 that outputs output data including the ROI image data 101a to the outside.

[0052] For example, in a system for detecting the state of a quantum bit, when image data capturing an image of the quantum bit is transferred to an external control system, the large amount of data transferred can make it difficult to increase the speed. This tendency is particularly pronounced in systems that simultaneously detect the states of a large number of quantum bits. In the quantum bit detection module 3 described above, output data including ROI image data 101a indicating the state of the quantum bit 105 is output to the outside of the module. Since the ROI image data 101a corresponds to the ROI 101, which is smaller than the imaging region 100 in the imaging unit 10, the data volume is smaller than the image data 100a corresponding to the imaging region 100. This reduces the amount of data output to the outside of the module, allowing data about the quantum bit 105 to be output at a high speed. In other words, the state detection of the quantum bit 105 can be accelerated.

[0053] In one example, the processing unit 20 can obtain composite image data 110 in which multiple ROI image data 101a corresponding to multiple ROIs 101 are composited together. In this configuration, there is no need to include additional information, such as address data and coordinate information, corresponding to the ROIs 101 in the output data. In this case, the amount of output data can be reduced. Furthermore, there is no need to perform processing to add address data and the like to the image data, thereby shortening the time required for output.

[0054] In one example, the processing unit 20 may combine the multiple ROI image data 101a with each other so as to maintain the arrangement order of the multiple ROIs 101 in the imaging region 100. In this configuration, the combined image data 110 is acquired in which the ROI image data 101a are combined in the original arrangement order. In this case, it is easy to grasp the state of each ROI 101 when visually checking the combined image data 110, for example.

[0055] One aspect of the quantum bit control system 1 includes a quantum bit control unit 30 that controls quantum bits 105 based on output data including ROI image data 101a output from quantum bit detection module 3. In one example, quantum bit control unit 30 controls quantum bits 105 based on position information of ROI 101 acquired separately from the output data including ROI image data 101a. That is, quantum bit control unit 30 identifies the position of quantum bits 105 in the output data based on the separately acquired position information of ROI 101. Because no position information is added to the output data from quantum bit detection module 3, data can be output at high speed.

[0056] Although the embodiment has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment.

[0057] For example, although an example in which one ROI includes the placement position of one quantum bit has been shown, this is not limiting. Figures 5 and 6 are schematic diagrams visually explaining the processing in the processing unit of other examples. In the examples of Figures 5 and 6, the ROI is set to include the placement positions of multiple quantum bits. For example, multiple quantum bits arranged in the X direction or Y direction may be included in one ROI. In this configuration, the number of times the ROI is extracted is reduced, thereby shortening the extraction processing time.

[0058] In the example of Fig. 5, the ROI 102 is a rectangle that surrounds a plurality of quantum bits 105 arranged in the X direction. In the example of Fig. 6, the ROI 103 is formed in a strip shape across the entire X direction so as to include a plurality of quantum bits 105 arranged in the X direction. In both Figs. 5 and 6, the image data corresponding to the ROI (ROI image data 102a, 103a) are extracted and then synthesized. As a result, one synthesized image data 120, 130 is formed.

[0059] 5 and 6, the image capture unit 10 may sequentially read out image data downward from the top row. In this type of readout method, the method of skipping the areas between quantum bits 105 arranged in the column direction can transfer data more efficiently than the method of skipping the areas between quantum bits 105 arranged in the row direction.

[0060] Also, although an example has been shown in which the composite image data is output from the output unit 25 to the quantum bit control unit 30, this is not limiting. For example, the processing unit 20 may cut out multiple pieces of second image data corresponding to multiple ROIs from the first image data, and the output unit may sequentially output each of the cut-out multiple pieces of second image data. That is, in the example of FIG. 4, ROI image data 101a may be output to the quantum bit control unit 30. In the example of FIG. 5, ROI image data 102a may be output to the quantum bit control unit 30. In the example of FIG. 6, ROI image data 103a may be output to the quantum bit control unit 30. In this configuration, data can be output for each ROI, so information on quantum bits 105 can be output without delay.

[0061] Although an example in which all ROIs have the same size has been shown, this is not limiting. For example, the processing unit 20 may adjust the size of the ROI depending on the position of the ROI within the imaging region 100. In one example, a relatively small ROI may be set in the center of the imaging region 100 of the imaging unit 10, and a relatively large ROI may be set in the edge portion of the imaging region 100. This configuration can correct image distortion in the image data 100a caused by a lens or the like. Note that if the sizes of the ROIs are different, the ROI image data may be normalized to unify the image sizes.

[0062] Although an example has been shown in which the processing unit 20 cuts out an ROI image from image data, for example, the imaging unit 10 may read out a region of the image sensor corresponding to the ROI so as to partially cut it out, and the read-out ROI image data may be sequentially sent to the processing unit 20. In this case, the imaging unit 10 may combine the multiple partially read-out ROI images and send the combined image data to the processing unit 20.

[0063] Furthermore, although an example has been shown in which filtering is performed in the processing unit 20, such filtering may be performed in the imaging unit 10 or the quantum bit control unit 30.

[0064] The image data output from the output unit 25 may be a 16-bit image, but in order to further reduce the amount of data to be transferred, the number of bits of the image data may be converted to a smaller value within a range that does not significantly affect the dynamic range. For example, the image data output from the output unit 25 may be a 12-bit image, an 8-bit image, or the like.

[0065] Furthermore, in the above embodiment, an example in which ROI 101 is rectangular has been shown, but ROI 101 is not limited to being rectangular. ROI may be any shape in plan view having a certain area that can contain quantum bits 105, such as a circle or a polygonal shape other than a rectangle. For example, if the ROI is circular, the user may specify the coordinates of the center position of the ROI and the diameter or radius of the ROI.

[0066] Furthermore, although an example has been given in which a neutral atom is used as a quantum bit, the quantum bit may be any atom whose state can be controlled by an external operation, for example, an ionized atom.

[0067] The embodiments of the present disclosure can be expressed as follows. [1] A quantum bit detection module comprising: an imaging unit that images an imaging region including a position of a quantum bit and generates first image data corresponding to the imaging region; a processing unit that sets a region of interest that is smaller than the imaging region and includes the position of the quantum bit, and cuts out second image data from the first image data corresponding to the set region of interest; and an output unit that outputs output data including the second image data to an external device. [2] The quantum bit detection module described in [1], wherein a plurality of regions of interest are provided, and the processing unit acquires third image data in which the plurality of second image data corresponding to the plurality of regions of interest are combined with each other, and the output unit outputs the third image data. [3] The quantum bit detection module described in [2], wherein the plurality of regions of interest are arranged in a predetermined arrangement order in the imaging region, and the processing unit combines the plurality of second image data with each other so as to maintain the arrangement order of the plurality of regions of interest in the imaging region. [4] The quantum bit detection module of [1], wherein a plurality of regions of interest are provided, the processing unit respectively cuts out a plurality of pieces of the second image data corresponding to the plurality of regions of interest from the first image data, and the output unit sequentially outputs each of the cut-out pieces of the second image data. [5] The quantum bit detection module of [1] to [4], wherein a plurality of positions of the quantum bits are provided, and the processing unit sets the region of interest to include the positions of the plurality of quantum bits. [6] The quantum bit detection module of any of [1] to [5], wherein the processing unit adjusts the size of the region of interest depending on the position of the region of interest within the imaging region. [7] A quantum bit control system comprising the quantum bit detection module of any of [1] to [6], and a quantum bit control unit that controls the quantum bit based on the output data including the second image data output from the quantum bit detection module.[8] The quantum bit control system according to [7], wherein the quantum bit control unit controls the quantum bit based on position information of the region of interest acquired separately from the output data including the second image data.

[0068] 1... quantum bit control system, 3... quantum bit detection module, 10... imaging unit, 20... processing unit, 25... output unit, 30... quantum bit control unit.

Claims

1. A quantum bit detection module comprising: an imaging unit that images an imaging area including a quantum bit placement position and generates first image data corresponding to the imaging area; a processing unit that sets a region of interest that is smaller than the imaging area and includes the quantum bit placement position, and cuts out second image data from the first image data that corresponds to the set region of interest; and an output unit that outputs output data including the second image data to the outside.

2. The quantum bit detection module of claim 1, wherein a plurality of regions of interest are provided, the processing unit acquires third image data in which a plurality of second image data corresponding to a plurality of the regions of interest are combined with each other, and the output unit outputs the third image data.

3. The quantum bit detection module of claim 2, wherein the plurality of regions of interest are arranged in a predetermined order in the imaging area, and the processing unit combines the plurality of second image data with each other so as to maintain the order of arrangement of the plurality of regions of interest in the imaging area.

4. The quantum bit detection module of claim 1, wherein a plurality of regions of interest are provided, the processing unit cuts out a plurality of second image data corresponding to the plurality of regions of interest from the first image data, and the output unit sequentially outputs each of the plurality of cut-out second image data.

5. A quantum bit detection module according to any one of claims 1 to 4, wherein a plurality of positions for the quantum bits are provided, and the processing unit sets the region of interest so as to include the positions for the plurality of quantum bits.

6. The quantum bit detection module of claim 1, wherein the processing unit adjusts the size of the region of interest depending on the position of the region of interest within the imaging region.

7. A quantum bit control system comprising: the quantum bit detection module according to claim 1; and a quantum bit control unit that controls the quantum bit based on the output data including the second image data output from the quantum bit detection module.

8. The quantum bit control system according to claim 7, wherein the quantum bit control unit controls the quantum bit based on position information of the region of interest obtained separately from the output data including the second image data.

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