Ion position control system and method

Abstract

The invention provides an ion position control system and method, and the system comprises a connection unit which is used for enabling N1 electrodes in a digital signal control region, which is used for generating a high-order potential well, of an ion trap to be connected to a switch module, so as to achieve the switching of voltage signals of the connected electrodes, and the digital signal control region comprises N electrodes; the control unit is used for controlling N2 electrode voltages in the digital signal control area, so that the high-order potential well is split into a plurality of sub-potential wells; and the adjusting unit is used for adjusting partial or all electrode voltages in the N1 electrodes connected to the switch module while the high-order potential well is split into a plurality of sub-potential wells, so as to control the ions in the high-order potential well or partial or all ions in the ion chain to be in the split appointed sub-potential well in the splitting process of the high-order potential well. According to the invention, a plurality of ion chains are trapped in a linear bound area, and the ion position can be controlled by a digital signal.

Description

Technical Field

[0001] The present invention belongs to the technical field of quantum computing, and in particular relates to a control system and method for ion positions. Background Art

[0002] Ion trap quantum computers are one of the possible routes to achieve large-scale quantum computing today. Among the possible expansion routes of ion trap quantum computers, the quantum charge coupled device (Quantum Charge Coupled Device) is a very promising expansion route that is being continuously promoted internationally. The characteristic of this route is to provide precise control of the position of ions (such as the movement of ions, the separation or merging of ion chains, the position exchange between ions, etc.) to reduce the crosstalk between ions, thereby making it possible to precisely control thousands of ion quantum bits. However, this requires a large number of DC voltage electrodes to achieve this. Therefore, the scalability of the electrical system is a very important issue in the quantum charge coupled device route.

[0003] In response to the above problems, Quantinuum submitted a paper titled "Scalable Multispecies Ion Transport in a Grid Based Surface-Electrode Trap" on the preprint website arXiv. In the existing technical solution of this paper, the left and right electrodes in a C2LR area are connected to a switch switching network (a switch switching network that receives multiple digital signals, switches the analog signal of the voltage source received by the DC voltage electrode, so that the analog signal of the voltage source can be reused). By switching the voltage connection method, the ions can be controlled to move left or right. Although this solution can ensure that the switch switching network is small in scale and realize the scalability of the electrical system, the implementation of this solution requires the voltage waveform of ion transport to be symmetric about the central electrode of the C2LR area as a prerequisite. However, for a general chip ion trap quantum computing system, if a complete QCCD control scheme is to be implemented, a straight line confinement area needs to have multiple ion spatial position selection areas. At this time, it is very difficult to make the voltage waveform of ion transport symmetric about multiple centers. Therefore, using a small-scale switch switching network to realize multiple ion spatial position selection areas in a linear confinement region remains an urgent problem to be solved. Summary of the invention

[0004] In view of the above problems, the present invention provides a control system and method for ion position, the method comprising:

[0005] A control system for ion positions, the method comprising:

[0006] A connection unit, used to connect N1 electrodes in a digital signal control area of ​​the ion trap for generating a high-order potential well to a switch module, so as to switch the voltage signal of the connected electrodes, wherein the digital signal control area includes N electrodes, N1≤N;

[0007] A control unit, used for controlling the voltages of N2 electrodes in the digital signal control area so as to split the high-order potential well into a plurality of sub-potential wells;

[0008] The regulating unit is used to regulate the electrode voltages of some or all of the N1 electrodes connected to the switch module while the high-order potential well is split into multiple sub-potential wells, so as to control the ions in the high-order potential well or some or all of the ions in the ion chain to be in the designated sub-potential well after the splitting during the high-order potential well splitting process, wherein N2≤N.

[0009] Furthermore, the ion trap includes a plurality of linear confinement regions, the linear confinement regions are connected by cross regions, and each linear confinement region includes a plurality of the digital signal control regions.

[0010] Furthermore, among the N electrodes, some electrodes are first connected to the output end of the switch module, the switch module is connected to the same power supply group, and the remaining electrodes are directly connected to the same power supply group.

[0011] Furthermore, among the N electrodes, all electrodes are first connected to the output end of the switch module, and the switch module is connected to the same power supply group.

[0012] Furthermore, among the N electrodes, all electrodes are first connected to the output end of the switch module, and the switch module is connected to the same power supply group.

[0013] Furthermore, the number of electrodes in each digital signal control area is the same or different.

[0014] Furthermore, the electrode voltage is regulated and controlled by:

[0015] The electrode voltage waveform is optimized in advance by using the optimization unit, and the electrode voltage is controlled by using the control unit according to the optimized voltage waveform, and the electrode voltage is adjusted by using the adjustment unit.

[0016] Furthermore, the electrode voltage waveform is optimized in advance, including:

[0017] Using the construction unit, construct the change process of the preset high-order potential well, define the preset loss function, and use each electrode voltage as a free parameter;

[0018] The optimization unit is used to optimize the free parameters to minimize the loss function and obtain the optimized voltage waveform.

[0019] On the other hand, the present invention also provides a method for controlling ion positions, the system comprising:

[0020] Connecting N1 electrodes in a digital signal control area of ​​the ion trap for generating a high-order potential well to a switch module to realize switching of voltage signals connected to the electrodes, wherein the digital signal control area includes N electrodes, N1≤N;

[0021] By controlling the voltages of N2 electrodes in the digital signal control area, the high-order potential well is split into multiple sub-potential wells. At the same time, by adjusting the voltages of some or all of the N1 electrodes connected to the switch module, the ions in the high-order potential well or some or all of the ions in the ion chain are controlled to be in the designated sub-potential well after the splitting during the high-order potential well splitting process, wherein N2≤N.

[0022] Furthermore, the ion trap includes a plurality of linear confinement regions, the linear confinement regions are connected by cross regions, and each linear confinement region includes a plurality of the digital signal control regions.

[0023] The present invention provides a control system and method for ion position, which can trap multiple ion chains in a linear confinement area while realizing digital signal control of ion position. The ion position change under digital signal control can be more varied and adapt to more complex application scenarios.

[0024] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief introduction is given below to the drawings to be used in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 A schematic diagram of functional partitioning of an ion trap according to an embodiment of the present invention is shown;

[0027] Figure 2 A schematic diagram showing the arrangement of electrodes in a linear confinement zone according to an embodiment of the present invention is shown;

[0028] Figure 3 shows an electrode voltage waveform diagram for generating a high-order potential well according to an embodiment of the present invention;

[0029] Figure 4 A basic principle diagram of four-potential-well separation according to an embodiment of the present invention is shown;

[0030] Figure 5 It shows the waveform change diagram of electrodes U1 to U5 and D1 to D5 when the digital signal 01 is input according to an embodiment of the present invention;

[0031] Figure 6 A diagram showing the separation of a potential well in which ions move to the left during four potential well separations according to an embodiment of the present invention is shown;

[0032] Figure 7 It shows the waveform change diagram of electrodes U1 to U5 and D1 to D5 when a digital signal 10 is input according to an embodiment of the present invention;

[0033] Figure 8 A diagram showing the separation of a potential well in which ions move to the left during four potential well separations according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] like Figure 1 As shown, the present invention provides a control system for ion positions, wherein the present invention can be applied to a chip-type ion trap, and the chip-type ion trap has a plurality of arms (also referred to as linear confinement regions), each linear confinement region (e.g. Figure 1 The area formed by the sub-areas labeled P1, W1, G, W2 and P2 in the box is a linear bound area) connected by the cross area (e.g. Figure 1 The sub-region is marked with J).

[0036] Figure 1 The straight line restraint area is only used to distinguish the area. It is not limited to these numbers. For example, in some embodiments of the present invention, the straight line restraint area is exemplified as Figure 2 There are three types of electrodes, one of which is named after the letter M, namely, M0, M1, M2, M3, M4, M5, M6, M7, M8, M9, M10, Ma and Mb. The arrangement of these electrodes can be referred to Figure 2, and with an electrode Ma as the center, both sides are arranged in the order of Mb, M0, M1, M2, M3, M4, M5, M6, M7, M8, M9 and M10. The second category is the electrodes U0, U1, U2, U3, U4, U5 and U6 named with the character U, and with an electrode U0 as the center, both sides are arranged in the order of U1, U2, U3, U4, U5 and U6. The third category is the electrodes D0, D1, D2, D3, D4, D5 and D6 named with the character D, and with an electrode D0 as the center, both sides are arranged in the order of D1, D2, D3, D4, D5 and D6.

[0037] in addition, Figure 1 Each linear confinement region shown has a plurality of sub-regions with corresponding labels, and each sub-region may have a plurality of electrodes. For example, Figure 1 The sub-region labeled P1 corresponds to Figure 2 The electrodes in the diagram are M7, M8, M9, and M10 on the left of Ma, U6 on the left of U0, and D6 on the left of D0; Figure 1 The sub-region labeled W1 corresponds to Figure 2 The electrodes in the figure are M1, M2, M3, M4 and M5 on the left of Ma, U1, U2, U3, U4 and U5 on the left of U0, and D1, D2, D3, D4 and D5 on the left of D0; Figure 1 The sub-region labeled G corresponds to Figure 2 The electrodes in the are U0, D0, Ma, Mb on the left and right sides of Ma, and M0 on the left and right sides; Figure 1 The sub-region labeled W2 corresponds to Figure 2 The electrodes in the figure are M1, M2, M3, M4 and M5 to the right of Ma, U1, U2, U3, U4 and U5 to the right of U0, and D1, D2, D3, D4 and D5 to the right of D0. Figure 1 The sub-region labeled P2 corresponds to Figure 2 The electrodes in the diagram are M6, M7, M8, M9 and M10 to the right of Ma, U6 to the right of U0, and D6 to the right of D0.

[0038] In the present invention, each linear binding area includes a plurality of the digital signal control areas. The digital signal control areas are as follows: Figure 1 Examples of Figure 1 In the P1, W1, G, W2 and P2 sub-areas, the electrodes in the digital signal control area are Figure 2Exemplary electrodes may include all numbered electrodes (including electrodes named by the characters M, U and D), which may be preset to be N electrodes. Among the N electrodes, some electrodes may be directly connected to the output end of the switch module first, and the switch module is connected to the same power supply group, and the remaining electrodes are directly connected to the same power supply group; or among the N electrodes, all electrodes may be first connected to the output end of the switch module, and the switch module is connected to the same power supply group.

[0039] In some embodiments of the present invention, it is assumed that the electrodes of the ion trap are distributed as follows: Figure 2 As shown, the two areas in the black dotted box are digital signal control areas. Moreover, after the electrodes labeled U and D are connected through a switch module controlled by a digital signal, the electrodes with the same label share a set of voltage sources. The remaining electrodes (electrodes labeled M) directly share the power supply with the same label.

[0040] The number of electrodes in each digital signal control area is the same or different and can be set as needed. For example, there can be 6 electrodes in the area where U0 is located and 7 electrodes in the area where U6 is located. However, the number of electrodes in U1-U5 is the same and can be 5 (but Figure 2 In the figure, U0 and U6 are one electrode).

[0041] The system of the present invention is described in detail below based on the above description.

[0042] The control system of ion position of the present invention comprises: a connection unit, which is used to connect N1 electrodes in the digital signal control area of ​​the ion trap for generating high-order potential wells to a switch module to realize the switching of the voltage signal of the connected electrodes, wherein the high-order potential wells include quartic potential wells and octapotent potential wells, etc., wherein the digital signal control area includes N electrodes, N1≤N.

[0043] The control unit is used to control the voltages of N2 electrodes in the digital signal control area so as to split the high-order potential well into a plurality of sub-potential wells.

[0044] The regulating unit is used to adjust the electrode voltages of some or all of the N1 electrodes connected to the switch module while the high-order potential well is split into multiple sub-potential wells, so as to control the ions in the high-order potential well or some or all of the ions in the ion chain to be in the designated sub-potential well after the splitting during the high-order potential well splitting process, wherein N2≤N.

[0045] In some embodiments of the present invention, the electrode voltage is regulated and controlled by:

[0046] The electrode voltage waveform is optimized in advance by using the optimization unit, and the electrode voltage is controlled by using the control unit according to the optimized voltage waveform, and the electrode voltage is adjusted by using the adjustment unit. The electrode voltage waveform is optimized in advance, including:

[0047] The construction unit is used to construct the change process of the preset high-order potential well, define the preset loss function, and take the voltages of each electrode as free parameters; then the optimization unit is used to optimize the free parameters so that the loss function is minimized and the optimized voltage waveform is obtained.

[0048] The method of the present invention is described below based on an example.

[0049] like Figure 2 As shown in FIG. 1 , the electrode labeled M is used to generate a high-order potential well to achieve the separation and merging of multiple ions or ion chains. Figure 3 The waveform shown (voltage waveform, the horizontal axis is time t, the vertical axis is DC electrode voltage) controls the 13 independent electrodes labeled M, and then a fourth potential well can be generated. These electrodes are directly connected to the power supply to achieve the following Figure 4 The potential wells shown are separated (the reverse process is merging), thereby achieving the separation / merging of ions or ion chains. Next, electrodes labeled U and D are introduced, and the voltages of these electrodes are controlled by digital signals, that is, these electrodes are first connected to the switch module and then to the power supply, wherein the specific behavior of the digital signal control is exemplified as follows:

[0050] When the digital signal input is 01, the U1 to U5 and D1 to D5 electrodes are as follows Figure 5 The waveform changes, U0, U6, D0, D6 electrodes are grounded, and the basic separation and merging potential well (the original high-order potential well) can be transformed into a left-direction selection potential well, such as Figure 6 As shown. Figure 6 When the digital signal is 10, the electrodes U1 to U5 and D1 to D5 are controlled as follows: Figure 7 The waveform changes, U0, U6, D0, D6 are grounded, and the basic separation and merging potential well (the original high-order potential well) can be transformed into a right-direction selection potential well, such as Figure 8 As shown. Figure 8 If you move the ion through the potential well, the ion will move to the right.

[0051] Based on the above description, the present invention realizes the control of the movement direction of ions by digital signals. At the same time, in order not to lose the separation / merging function, the present invention introduces: when the digital signal input is 11, the electrodes labeled U and D are switched to ground (i.e., 0V), then the potential well felt by the ions is Figure 4 Consistent, normal separation and merging operations can be achieved.

[0052] In addition, if a higher-order potential well is considered, the M-labeled electrode generates an eight-order potential well. By adjusting the corresponding voltage electrode, one potential well is split into three, and the middle one remains stationary. After introducing the assistance of U and D-labeled electrodes, the present invention can realize digital signal control of the movement states of more ions. In addition to the above-mentioned movement of ions to the left or right, ions can also be made to stay in place. The additional choice of movement states can make ion manipulation more flexible and more parallel.

[0053] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A control system for ion positions, characterized in that: The method comprises: A connection unit, used to connect N1 electrodes in a digital signal control area of ​​the ion trap for generating a high-order potential well to a switch module, so as to switch the voltage signal of the connected electrodes, wherein the digital signal control area includes N electrodes, N1≤N; A control unit, used for controlling the voltages of N2 electrodes in the digital signal control area so as to split the high-order potential well into a plurality of sub-potential wells; The regulating unit is used to regulate the electrode voltages of some or all of the N1 electrodes connected to the switch module while the higher-order potential well is split into multiple sub-potential wells, so as to control the ions in the higher-order potential well or some or all of the ions in the ion chain to be in the designated sub-potential well after the splitting during the splitting of the higher-order potential well, wherein N2≤N.

2. The ion position control system according to claim 1, characterized in that: The ion trap includes a plurality of linear confinement regions, the linear confinement regions are connected by cross regions, and each linear confinement region includes a plurality of the digital signal control regions.

3. The ion position control system according to claim 1, characterized in that: Among the N electrodes, some electrodes are first connected to the output end of the switch module, the switch module is connected to the same power supply group, and the remaining electrodes are directly connected to the same power supply group.

4. The ion position control system according to claim 1, characterized in that: All the N electrodes are first connected to the output end of the switch module, and the switch module is connected to the same power supply group.

5. The ion position control system according to claim 1, characterized in that: All the N electrodes are first connected to the output end of the switch module, and the switch module is connected to the same power supply group.

6. An ion position control system according to any one of claims 3 to 5, characterized in that: The number of electrodes in each digital signal control area is the same or different.

7. The ion position control system according to claim 6, characterized in that: The electrode voltage can be regulated and controlled by: The electrode voltage waveform is optimized in advance by using the optimization unit, and the electrode voltage is controlled by using the control unit according to the optimized voltage waveform, and the electrode voltage is adjusted by using the adjustment unit.

8. The ion position control system according to claim 7, characterized in that: Pre-optimize the electrode voltage waveform, including: Using the construction unit, construct the change process of the preset high-order potential well, define the preset loss function, and use each electrode voltage as a free parameter; The optimization unit is used to optimize the free parameters to minimize the loss function and obtain the optimized voltage waveform.

9. A method for controlling ion position, characterized in that: The system comprises: Connecting N1 electrodes in a digital signal control area of ​​the ion trap for generating a high-order potential well to a switch module to realize switching of voltage signals connected to the electrodes, wherein the digital signal control area includes N electrodes, N1≤N; By controlling the voltages of N2 electrodes in the digital signal control area, the high-order potential well is split into multiple sub-potential wells. At the same time, by adjusting the voltages of some or all of the N1 electrodes connected to the switch module, the ions in the high-order potential well or some or all of the ions in the ion chain are controlled to be in the designated sub-potential well after the splitting during the high-order potential well splitting process, wherein N2≤N.

10. The method for controlling ion positions according to claim 9, characterized in that: The ion trap includes a plurality of linear confinement regions, the linear confinement regions are connected by cross regions, and each linear confinement region includes a plurality of the digital signal control regions.

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