Secure solid-state quantum storage

Abstract

To provide a system and a method for creating and reading a secure solid-state quantum storage.SOLUTION: A system includes an illumination source and a detection system, and the illumination source provides excitation light to a quantum memory array, and the detection system detects emission light from the quantum memory array, and the emission light corresponds to a plurality of qubits stored in the quantum memory array.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Cross - Reference to Related Applications

[0001] This application is a non - provisional application of U.S. Provisional Patent Application No. 63 / 621,415, entitled "SECURE SOLID - STATE QUANTUM STORAGE DEVICES", filed on January 16, 2024, which is hereby incorporated by reference in its entirety into this specification.

Background Art

[0002]

[0002] The limitations and drawbacks of conventional memory devices will become apparent to those skilled in the art through a comparison of such approaches with some aspects of the methods and systems of the present disclosure described below with reference to the drawings.

Summary of the Invention

[0003]

[0003] A system and method for fabricating and reading a secure solid - state quantum memory device are provided as substantially shown and / or described in connection with at least one of the figures and more fully described in the claims.

Brief Description of the Drawings

[0004]

Figure 1

[0004] A top view of an exemplary wafer with a quantum memory array embedded according to various exemplary embodiments of the present disclosure.

Figure 2

[0005] A side view of an exemplary wafer with a quantum memory array embedded according to various exemplary embodiments of the present disclosure.

Figure 3

[0006] A diagram showing an exemplary process flow for fabricating a quantum memory array according to various exemplary embodiments of the present disclosure.

Figure 4

[0007] A diagram showing an example of ion implantation in a quantum memory array according to various exemplary embodiments of the present disclosure.

Figure 5

[0008] FIG. 0 is a diagram showing an exemplary quantum memory array readout system having a micro-LED illumination array and a 2D imager according to various exemplary embodiments of the present disclosure.

Figure 6

[0009] FIG. 5 is a diagram showing an exemplary quantum memory array readout system having a holographic excitation source according to various exemplary embodiments of the present disclosure.

Figure 7

[0010] FIG. 9 is a diagram showing an exemplary quantum memory array readout system having front illumination and back illumination and a 3D holographic position mapper according to various exemplary embodiments of the present disclosure.

Figure 8

[0011] FIG. 13 is a diagram showing details of an exemplary secure decoder according to various exemplary embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0005]

[0012] The present disclosure describes processes for the artificial generation and detection of defects in a substrate. These processes enable the encoding, storage, and decoding of data via a quantum memory array. The generation of defects is achieved by high-energy ion implantation or high-power focused short light pulses. The quantum memory may use ultra-wideband bandgap semiconductors (UWBGS) such as silicon carbide (SiC), gallium nitride (GaN), gallium oxide (GaO), boron nitride (BN), diamond, etc.

[0006]

[0013] The quantum memory utilizes color centers (atomic point defects in UWBGS materials) to store stable quantum states even in harsh environments. SiC offers advantages such as larger wafer size and lower native defect density compared to other materials.

[0007]

[0014] The disclosed quantum memory system encodes information and enables secure and high-density storage. Quantum bits are embedded in predetermined color centers arranged in a 2D grid with multiple depth levels to facilitate advanced encoding methods.

[0008]

[0015] The quantum memory array may be integrated with a quantum computing system, and the quantum memory array includes a plurality of quantum color centers aligned with a qubit processor.

[0016] Figures 1 and 2 show the structure of the UWBGS wafer and the arrangement of qubits in a multi-level grid. These figures provide insights into material properties and encoding configurations. Figure 1 shows a top view of a wafer having a 2D quantum memory array. Figure 2 provides a side view showing depth-level encoding within the array. Encoding

[0017] Figure 3 shows an exemplary process flow for fabricating a quantum memory array according to various exemplary embodiments of the present disclosure. This wafer-level manufacturing process may enable high-areal density quantum memories through secure encoding and printing.

[0009]

[0018] Figure 3 also includes an example of an ion implantation process, highlighting the role of the photomask, depth-specific implantation, and annealing processes. Also, in the writing process, a programmable depth-focused high-power pulsed laser can be utilized on the wafer, with or without a photomask. These figures emphasize the accuracy required for encoding.

[0010]

[0019] The wafer can be SiC, diamond, or another similar material. At 301, an optical metal mask is deposited on the wafer. The mask provides a spatial distribution, for example, as shown in Figure 1. The mask is depicted with encoded secure information. Multiple patterned masks can be used to transfer information at different depths to the memory array.

[0011]

[0020] At 303, ions are implanted into the wafer to create detectable defects. Helium (He) can be used for implantation into SiC. Depending on the desired defect structure and the resulting properties of the color centers, other ions such as hydrogen (H+) and nitrogen (N+) or atomic color center impurities such as vanadium (Va) may be used.

[0012]

[0021] Different ion energy levels can generate defects at different levels. In each iteration of 303, different energies are used to provide depth coordinates as shown, for example, in Figure 2. For example, 303 may be repeated to result in the formation of each layer of N-layer pixels. An example of the ion implantation process with N = 3 is shown on the right side of Figure 3. These pixels can be data-encoded qubits associated with a security key. Defects can be created simultaneously at multiple positions in the x and y dimensions across the wafer through the ion implantation process. Multiple masks can be generated and aligned with each other at sub-micron resolution to obtain an ultra-high areal density. Multi-level implantation with multiple different ion implantation energies may be used to generate defects at predefined positions and depths. A combination of multiple masked implantations may provide grayscale encoding at the positions of the specified regions.

[0013]

[0022] In 305, the mask is removed from the implanted wafer. After N iterations of 301, 303, and 305, annealing in 307 completes the multi-valued quantum memory and immobilizes the encoded data.

[0014]

[0023] Secure encoding is achieved by encrypting data within the storage pixels and dispersing the bits across multiple depths and locations. An advanced encoding process can be used to disperse binary data into an encrypted format.

[0015]

[0024] Additional methods such as high-energy radiation or impurity implantation can enhance the generation of color centers. Parameters such as ion energy and ion dose amount affect the depth, emission luminance, and emission wavelength from a given color center, and can ensure high stability and resistance to external interference. The following table shows examples of ion implantation energies and dose amounts that can be used with He ions.

[0016]

Table 1

[0017]

[0025] The implantation process results in a damage profile with a lateral spread. The pixel placement is determined by the ion energy and the dose amount, and sufficient separation can be ensured to avoid signal overlap.

[0018]

[0026] Figure 4 shows examples of the lateral depth, lateral spread, and lateral straggle of He ion implantation in a quantum memory array according to various exemplary embodiments of the present disclosure. Figure 4 models an energy level of 50 keV and a dose amount of 1×10 14 / cm 2 .

[0019]

[0027] When ions are implanted into a crystal, they decelerate until they reach a specific depth and then stop, forming a damage profile similar to a Gaussian curve.

[0028] At high-intensity peaks, the dose amount may spread over a range, for example, from 1000 to 3000 angstroms. This movement of ions parallel to the wafer surface as a result of ion implantation is shown by the lateral straggle curve. The curves of lateral depth and lateral spread show other depths.

[0020]

[0029] Despite the potential for blurring by adjacent pixels, slight differences in intensity enable information restoration using advanced encoding and decoding techniques. However, the maximum feature density can be restricted by the lateral spread that depends on the ion energy. For example, as a result, a zone of 100 nanometers occurs for each straggle, and the pitch between two features can be about 200 nanometers. This interval defines the maximum density of the imprint and can enable reading color centers with high accuracy.

[0021]

[0030] In addition to the precision and accuracy obtained by ion implantation, the present disclosure also enables resistance to forgery by encryption technology. Instead of simply generating color centers for each bit of data, the data is dispersed to multiple positions and depths by encryption.

[0022]

[0031] For example, when preparing a photomask, the original binary data (e.g., "0" or "1") can be encrypted using a key to shuffle or stretch the data bits and assign them across various positions, depths, and colors. This ensures that only authorized users with the correct detection color filter and decryption key can access and reconstruct the data, enhancing the security and robustness of quantum memory applications.

[0023]

[0032] The encoder can encrypt the received data, generate a spatially encoded implant mask, and control the corresponding energy and dose of the ion implantation device. When different color center impurities are implanted, specific wavelengths of excitation light and related detection color filters may be required to excite and observe a given quantum transition. The encoded data can be transferred and printed onto a photomask. The pattern of the photomask may be transferred and drawn onto a hard implant mask on the surface of the semiconductor substrate. The implant mask may allow ions or pulsed laser light to pass through open pixel positions to generate color centers while blocking non-memory regions. Different masks may be overlaid on each other to provide different implantation depths at different positions. Decryption

[0033] The decryption of the quantum memory relies on optical excitation to extract data from multiple color centers. Excitation using a specific wavelength triggers emission and enables the reading of the stored information. The emission rate of the color centers is less than 10 nanoseconds, enabling rapid data acquisition. The detection system may be configured to detect the emitted light from the pixels of the quantum memory array, and the emitted light can be decoded into multiple qubits.

[0024]

[0034] FIG. 5 shows an exemplary quantum memory array readout system having a micro-LED illumination array and a 2D imager according to various exemplary embodiments of the present disclosure. The wavelength of the illumination source can excite the color centers from the ground state to the excited quantum state. The wavelengths of the color filter and the detector can detect the characteristic emission light of a given color center. For example, a 781 nm excitation light and a 940 - 950 nm detector are used to read out the written He-implanted SiC color centers. FIG. 6 shows an exemplary quantum memory array readout system having a holographic excitation source according to various exemplary embodiments of the present disclosure. FIG. 7 shows an exemplary quantum memory array readout system having front illumination and back illumination and a 3D holographic position mapper according to various exemplary embodiments of the present disclosure.

[0025]

[0035] Each of the readout systems of FIGS. 5 - 7 is shown together with a quantum memory wafer 501. Each of the readout systems of FIGS. 5 - 7 includes a unique illumination source (described in further detail below in connection with each figure), a lens 503, an imager 505, a secure decoder 507, and a security key 509. FIG. 8 shows the details of an exemplary secure decoder 507 according to various exemplary embodiments of the present disclosure. To increase security and memory density, multiple types of color centers can be written to the wafer. Detection of multiple types of color centers may require different excitation light sources, color filters, and / or detectors to read the data stored in each type of color center in order to assemble and collate the information.

[0026]

[0036] The readout systems of FIGS. 5 - 7 can use a serial scan to pick up the excited qubits. Similar to a CD-ROM, the serial scan includes a sequential read head that addresses each memory pixel (one by one) and a synchronized mechanical rotating substrate, and can read the bits stored in the x - y dimensions.

[0027]

[0037] The lens 503 and the imager 505 (e.g., a CMOS camera) can be used to record the emitted light of the memory array in the light collection region. The secure decoder 507 can use direct 2D secure reading or digital 3D holographic secure reading. In direct 2D secure reading, the secure decoder 507 can use the security key 509 to decode the intensity of the 2D emitted light from the x-y array, as shown in FIG. 8.

[0028]

[0038] In digital 3D holographic secure reading, the secure decoder 507 can first retrieve the information stored holographically in 3D from 2D positions with corresponding intensities. The secure decoder 507 can then map the data to 3D defect positions. Temporally secure position-coded data can be decoded to the original information using the security key 509. This enables the encoding and decoding of secure information through programmed defects spatially distributed over various x-y and depth positions.

[0029]

[0039] The illumination source can be configured to supply excitation light to the quantum memory array of the quantum memory wafer 501. The illumination source can be, for example, a laser, a light-emitting diode (LED), or a micro-LED array. The illumination source can be a pulsed source and a continuous wave (CW) source.

[0030]

[0040] In FIG. 5, the illumination source comprises a micro-LED array 511 and a programmable security element 513, e.g., one or more keys or watermarks.

[0041] In FIG. 6, the illumination source comprises a laser 601, a programmable diffraction optical system 603, and a programmable security element 605. The programmable diffraction optical system 603 can be configured to project 3D holographic keys and / or watermarks that can excite 3D color centers (e.g., at different depths) via the programmable security element 605.

[0031]

[0042] The programmable diffractive optical system 603 can include a planar multi-layer optical waveguide having a plurality of layers. The planar multi-layer optical waveguide can be configured to guide excitation light and collect emitted light. The planar multi-layer optical waveguide may be directly deposited on the quantum memory array 501.

[0032]

[0043] In FIG. 7, the illumination source includes a back-illumination light source (or light source array) 701 and a front-illumination light source (or light source array) 703 to supply energy above and below the wafer 501. The excitation light can be continuous wave (CW), or may be pulsed with or without a code. The illumination light can be supplied to the front 703 or back 701 of the substrate, or supplied to the edge using a distribution waveguide. The illumination source (701 and / or 703) can include a 2D addressable micro-LED or a laser array that matches the memory pixel layout. The pixels can be illuminated one by one or multiple pixels at a time. A single illumination source (701 and / or 703) may be split into two or more beams.

[0033]

[0044] The emitted light from the written three-dimensional quantum defect can be detected by an intensity-based digital holographic position mapper 705. The digital holographic position mapper 705 can store the x-y position and intensity of the detected light in a data buffer.

[0034]

[0045] The read process can be performed sequentially or in parallel using an imaging array. A high-performance CMOS imager can operate, for example, at 100 million frames per second and achieve a read rate of up to 1 petabit per second. Parallel detection and optimized decoder electronics can improve the overall read rate and relax potential speed limitations.

[0035]

[0046] Quantum memory systems are mainly designed for read-only use, and the decay time can range from nanoseconds to microseconds. These characteristics ensure reliable data acquisition while minimizing problems related to decay. Although the read rate may be slightly reduced by the coding overhead, the high speed of quantum memory remains unparalleled.

[0036]

[0047] The maximum memory density depends on the size of each pixel. The physical size of each pixel can be limited by the dimensions of the lithography process of the implantation mask and the lateral straggle (spread) of the implanted ions (e.g., 100 nm at 50 keV), whereby a pixel size on the order of 0.35 microns × 0.35 microns may be obtained. The pixel size can be further reduced, for example, to 0.2 microns × 0.2 microns by applying an error correction code.

[0037]

[0048] A plurality of planar optical waveguide layers can be deposited on the wafer in the x-y plane. Grating couplers may be incorporated at the intersections of the waveguides for vertically incident and reading light. At the inputs of the x and y waveguides, optical switches can be used so that each pixel can be individually addressed. A 2D liquid crystal on silicon (LCOS) switch with individually addressable pixels can be used to selectively read light from the corresponding memory bits in the array.

[0038]

[0049] The light intensity and the holographic pattern can be calibrated and self-adjusted with respect to a set of predetermined coded patterns on the wafer before detection and decoding.

[0050] For the sequential reading and decoding of sequentially encoded information, security is embedded and may spread across several sequential bits. The sequential reading system can read and capture the read bits of the required length before decoding. By incorporating some overhead bits, this can provide error correction coding.

[0039]

[0051] In a state where the micro-LED array is aligned with the quantum color center storage array, a specific turn-on pattern for each pixel of the 2D micro-LED array can accumulate the intensity from the superimposed 3D color centers. The holographic emitter can illuminate the 3D color center array and access depth information by exciting individually addressed pixels at a predetermined depth. An adjustable excitation light source, color filter, and broadband detector can extract the information stored between the mixed types of color centers.

[0040]

[0052] The detection system can be configured to resolve the wavelength and / or polarization of the emitted light. The detection system can be configured to resolve the overlapping signals of the emitted light according to a machine learning algorithm.

[0041]

[0053] The detection system can include an optical isolator or spread coder that reduces the signal overlap between adjacent pixels. The optical isolator or coder can include a multilayer interference filter and / or a spatial light modulator that dynamically adjusts the density and position of the emitted light.

[0042]

[0054] The detection system can include a data reconstruction module that is calibrated for pixel intensity variations caused by differences in injection depth. The various frequency components of the emitted light from different types of color centers can be aggregated and decoded by data processing. The non-linearity of the emitted light signal can be compensated using polynomial regression.

[0043]

[0055] The readout system described herein can operate at room temperature. When integrated with a qubit quantum detector, a cooled photodetector can also be used.

[0056] Although the method and / or system have been described with reference to particular embodiments, it will be understood by those skilled in the art that various changes and substitutions by equivalents may be made without departing from the scope of the method and / or system. Furthermore, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from its scope. Accordingly, the method and / or system are not limited to the particular embodiments disclosed, but it is intended that the method and / or system cover all embodiments falling within the scope of the appended claims.

Claims

1. An illumination source configured to supply excitation light to a quantum memory array, A detection system configured to detect emitted light from the quantum memory array, wherein the emitted light corresponds to a plurality of qubits stored in the quantum memory array, and the detection system A system including.

2. The system according to claim 1, The quantum memory array includes a plurality of pixels, Each pixel of the plurality of pixels is associated with a pixel size determined according to ion implantation energy and ion dose amount, System.

3. The system according to claim 1, The excitation light includes one or more wavelengths, Each of the one or more wavelengths corresponds to a different type of color center, System.

4. The system according to claim 1, wherein the illumination source is one of a laser, a light emitting diode (LED), and a micro LED array.

5. The system according to claim 1, wherein the illumination source is one of a pulse source and a continuous wave source.

6. The system according to claim 1, The illumination source is configured to supply the excitation light under a transparent substrate, System.

7. The system according to claim 1, The system includes a planar multi-layer optical waveguide including a plurality of layers deposited on the quantum memory array, The planar multi-layer optical waveguide is configured to guide the excitation light and collect the emitted light, System.

8. The system according to claim 1, The excitation light corresponds to a watermark, System.

9. The system according to claim 1, The detection system includes a secure decoder, The plurality of qubits are scrambled by diffusion across the quantum memory array, The secure decoder is configured to decode the plurality of qubits according to one or more encryption keys according to the spatial distribution and intensity of the emitted light, System.

10. The system according to claim 9, The secure decoder is configured according to one or both of 2D reading and 3D holographic reading, System.

11. The system according to claim 1, The quantum memory array includes a plurality of pixels, Each pixel of the plurality of pixels is associated with a pixel size determined according to the intensity and depth of focus of a high-energy pulsed laser. System. **Claim 12** The system according to claim 1, wherein the detection system includes one or both of a 2D imager and a CMOS camera. System. **Claim 13** The system according to claim 1, wherein the detection system is configured to resolve one or both of the wavelength and polarization of the emitted light. System. **Claim 14** The system according to claim 1, wherein the detection system is configured to resolve one or both of the overlapping signals and scrambled signals of the emitted light according to a machine learning algorithm. System. **Claim 15** The system according to claim 14, wherein the machine learning algorithm is configured according to a security key. System. **Claim 16** The system according to claim 1, wherein the quantum memory array includes a plurality of pixels, and the detection system includes an optical isolator configured to reduce the overlap of signals related to adjacent pixels among the plurality of pixels. System. **Claim 17** The system according to claim 16, wherein the optical isolator includes a coder having a spatial light modulator configured to dynamically adjust the emitted light. System. **Claim 18** The system according to claim 16, wherein the optical isolator includes a plurality of layers of interference filters. System. **Claim 19** The system according to claim 1, wherein the quantum memory array includes a plurality of pixels, and the detection system includes a data reconstruction module calibrated for fluctuations in pixel intensity and wavelength. System. **Claim 20** The system according to claim 1, wherein the detection system is configured to correct the non-linearity of the emitted light signal using polynomial regression. System.

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