Probabilistic bit device based on the dipole moment of a single tetraligand molecule and its preparation method

Abstract

The present invention relates to the field of single-molecule device technology, and in particular to a probabilistic bit device based on a single tetraligand molecular dipole moment and a preparation method thereof. A single tetraligand dipole molecule is assembled between a pair of graphene dot electrodes. The single tetraligand dipole molecule has good randomness or uncertainty characteristics, and the state of the molecule can be read by conductance, thereby realizing a probabilistic bit at the single-molecule scale. The present application utilizes the voltage dependence of molecular dipole reversal to establish a linear mapping relationship between the bistable time proportion and the bias parameter, breaking through the random generation mode of traditional probabilistic bits. The dynamics of molecular configuration is used as the core control dimension, and the device has both high-sensitivity field response and long-term coherence characteristics, providing an efficient and scalable hardware carrier for quantum-classical hybrid computing. The preparation method provided by the present invention has a simple process, mild reaction conditions, and is conducive to large-scale production.

Description

Technical Field

[0001] The present invention relates to the technical field of single-molecule devices, and in particular to a probabilistic bit device based on the dipole moment of a single tetraligand molecule and a preparation method thereof. Background Art

[0002] In traditional computing systems, the basic unit of information is the classical bit, whose binary nature (0 or 1) forms the logical foundation of deterministic computation. As computing needs become increasingly complex, quantum computing has proposed quantum bits (qubits) based on quantum superposition and entanglement, aiming to achieve breakthroughs in computing power through parallelism. However, the implementation of qubits is limited by the stringent requirements of quantum environments (such as ultra-low temperatures and decoherence effects), and their physical carriers (such as superconducting circuits and ion traps) often rely on complex peripheral control systems, limiting the feasibility of large-scale applications. Meanwhile, the concept of probabilistic bits has been proposed. These bits simulate non-deterministic state outputs through random processes, demonstrating unique value in the stochastic decision-making of classical algorithms (such as Monte Carlo simulations and genetic algorithms) and in quantum-classical hybrid computing. However, existing probabilistic bit implementations often rely on random number generation using electronic circuits or post-processing algorithms, which suffer from limitations in the source of randomness, low controllability, and insufficient energy efficiency.

[0003] In recent years, molecular devices have become a research hotspot for novel computing vehicles due to their unique physicochemical properties. The multiple degrees of freedom of molecular systems (such as electronic states, configurations, and dipole orientations) can provide natural randomness for information encoding. Their nanoscale self-assembly capabilities and low energy consumption have opened up new avenues for high-density integration and device miniaturization. In particular, in the field of dipole control, molecular systems with reversible configurational changes can be driven by external fields to achieve dipole reversal, forming bistable probabilistic outputs that are dependent on the applied bias voltage, offering a potential solution for the physical realization of probabilistic bits. Summary of the Invention

[0004] The present invention aims to address at least one of the technical problems existing in the related art. To this end, the first object of the present invention is to provide a probabilistic bit device based on the dipole moment of a single tetraligand molecule; the second object of the present invention is to provide a method for preparing a probabilistic bit device based on the dipole moment of a single tetraligand molecule.

[0005] In order to achieve the first purpose, the technical solution adopted by the present invention is:

[0006] A probabilistic bit device based on a single tetraligand molecular dipole moment comprises a first graphene point electrode, a molecular bridge, and a second graphene point electrode connected in sequence, wherein the first graphene point electrode and the second graphene point electrode form a graphene point electrode pair, and the molecular bridge is connected to the first graphene point electrode and the second graphene point electrode via an amide bond, respectively, and the molecular bridge serves as a functional unit for probabilistic bit regulation;

[0007] The molecular bridge is selected from a single tetradentate dipole molecule, and the single tetradentate dipole molecule is selected from a copper complex.

[0008] Furthermore, the single tetraligand dipole molecule is selected from any one of the following structural formulas:

[0009] 、

[0010] 、

[0011] .

[0012] Furthermore, the first graphene point electrode and the second graphene point electrode are nanogap point electrodes.

[0013] Furthermore, it also includes a first metal electrode and a second metal electrode, the first metal electrode is evaporated on the first graphene point electrode, the second metal electrode is evaporated on the second graphene point electrode, and the first metal electrode and the second metal electrode form a metal electrode pair.

[0014] Furthermore, the first metal electrode and the second metal electrode are selected from gold electrodes.

[0015] Furthermore, a protective layer is included, and the protective layer covers the metal electrode pair and the graphene point electrode pair.

[0016] Furthermore, the protective layer is made of hexagonal boron nitride.

[0017] In order to achieve the second purpose, the technical solution adopted by the present invention is:

[0018] A method for preparing a probabilistic bit device based on a single tetraligand molecular dipole moment, for preparing any of the above-mentioned probabilistic bit devices based on a single tetraligand molecular dipole moment, comprises the following steps:

[0019] S100, preparing a single layer of graphene on a backing by using a chemical vapor deposition method and an oxygen plasma etching method;

[0020] S200, preparing a graphene array electrode on the single-layer graphene by using photolithography technology and peroxide plasma etching technology;

[0021] S300, using electron beam exposure and etching technology to prepare a first graphene point electrode and a second graphene point electrode on the graphene array electrode, and performing oxygen plasma etching on the first graphene point electrode and the second graphene point electrode to obtain a graphene nanogap point electrode pair;

[0022] S400, placing the graphene nanogap point electrode pair and the tetraligand dipole compound in a reaction system, allowing the single tetraligand dipole molecule to self-assemble with the graphene nanogap point electrode pair, and obtaining a probabilistic bit device based on the dipole moment of the single tetraligand molecule.

[0023] Furthermore, in step S400, the reaction system includes a catalyst and a reaction solvent, the catalyst is selected from 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, and the reaction solvent is selected from pyridine.

[0024] Furthermore, the concentration of the tetraligand dipole compound in the reaction system is ≥0.5 mM.

[0025] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0026] The present invention provides a probabilistic bit device based on the dipole moment of a single tetraligand molecule and a preparation method. The probabilistic bit device assembles a single tetraligand dipole molecule between a pair of graphene point electrodes. The single tetraligand dipole molecule has good randomness or uncertainty characteristics, and the state of the molecule can be read by conductivity, thereby realizing a probabilistic bit at the single-molecule scale. The single tetraligand dipole molecule acts as a molecular bridge and is connected to the first graphene point electrode and the second graphene point electrode through an amide bond, which significantly enhances the chemical stability of the device, thereby ensuring the long-term reliability of the probabilistic bit device under complex operating conditions. The probabilistic bit device based on the dipole moment of a single tetraligand molecule achieves significant miniaturization of the device size and exhibits extremely high integration, providing new ideas for the miniaturization and high-density integration of functional chips, and laying a technical foundation for the future development of micro-nanoelectronics.

[0027] This application leverages the voltage dependence of molecular dipole reversal to establish a linear mapping between the bistability time fraction and the bias parameter. This breakthrough breaks through the random generation model of traditional probabilistic bits and uses molecular configuration dynamics as the core control dimension. This device combines highly sensitive field response with long-term coherence, providing an efficient and scalable hardware platform for quantum-classical hybrid computing. Compared to existing technologies, this invention offers significant advantages in device stability, energy efficiency, and external field controllability.

[0028] The preparation method provided by the invention has a simple process and mild reaction conditions, and is conducive to large-scale production.

[0029] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic structural diagram of a probabilistic bit device based on the dipole moment of a single tetraligand molecule provided by an embodiment of the present invention.

[0031] Figure 2 This is the distribution of the conductivity high and low state swings and their time proportions of the probabilistic bit device based on the dipole moment of a single tetraligand molecule under a bias voltage of 0.45V when the tetraligand dipole compound provided in Example 2 of the present invention is compound III.

[0032] Figure 3 This is the time proportion of the probabilistic bit device in high and low states at different bias voltages based on the dipole moment of a single tetraligand molecule when the tetraligand dipole compound provided in Example 2 of the present invention is compound III.

[0033] Figure 4 This is the distribution of the conductivity high and low state swings and their time proportions of the probabilistic bit device based on the dipole moment of a single tetraligand molecule under a bias voltage of 0.45V when the tetraligand dipole compound provided in Example 2 of the present invention is compound II.

[0034] Figure 5 This is the time proportion of the probabilistic bit device in high and low states at different bias voltages based on the dipole moment of a single tetraligand molecule when the tetraligand dipole compound provided in Example 2 of the present invention is compound II.

[0035] Figure 6 This is the distribution of the high and low state swings of conductivity and their time proportions of the probabilistic bit device based on the dipole moment of a single tetraligand molecule under a bias voltage of 0.45V when the tetraligand dipole compound provided in Example 2 of the present invention is compound IV.

[0036] Figure 7 This is the time proportion of the probabilistic bit device in high and low states at different bias voltages based on the dipole moment of a single tetraligand molecule when the tetraligand dipole compound provided in Example 2 of the present invention is compound IV.

[0037] Reference numerals:

[0038] 11. First graphene point electrode; 12. Second graphene point electrode; 2. Molecular bridge; 31. First metal electrode; 32. Second metal electrode; 4. Protective layer. DETAILED DESCRIPTION

[0039] To make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the embodiments described are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0040] like Figure 1 As shown, a probabilistic bit device based on a single tetraligand molecular dipole moment includes a first graphene point electrode 11, a molecular bridge 2, and a second graphene point electrode 12 connected in sequence. The first graphene point electrode 11 and the second graphene point electrode 12 form a graphene point electrode pair. The molecular bridge 2 is connected to the first graphene point electrode 11 and the second graphene point electrode 12 via an amide bond, respectively. The molecular bridge serves as a functional unit for probabilistic bit regulation.

[0041] The molecular bridge is selected from a single tetradentate dipole molecule, and the single tetradentate dipole molecule is selected from a copper complex;

[0042] The single tetraligand dipole molecule is selected from any one of the following structural formulas:

[0043] 、

[0044] 、

[0045] .

[0046] According to a specific embodiment provided by the present invention, the probabilistic bit device based on the dipole moment of a single tetraligand molecule also includes: a first metal electrode 31 and a second metal electrode 32, the first metal electrode 31 is evaporated on the first graphene point electrode 11, and the second metal electrode 32 is evaporated on the second graphene point electrode 12, and the first metal electrode 31 and the second metal electrode 32 form a metal electrode pair.

[0047] According to a specific embodiment provided by the present invention, the first metal electrode 31 and the second metal electrode 32 are selected from gold electrodes.

[0048] According to a specific embodiment provided by the present invention, the probabilistic bit device based on the dipole moment of a single tetraligand molecule further includes a protective layer 4, which covers the metal electrode pair and the graphene dot electrode pair.

[0049] According to a specific embodiment provided by the present invention, the protective layer 4 is made of hexagonal boron nitride.

[0050] A method for preparing a probabilistic bit device based on the dipole moment of a single tetraligand molecule comprises the following steps:

[0051] S100, preparing a single layer of graphene on a backing by using a chemical vapor deposition method and an oxygen plasma etching method;

[0052] S200, preparing a graphene array electrode on the single-layer graphene by using photolithography technology and peroxide plasma etching technology;

[0053] S300, using electron beam exposure and etching technology to prepare a first graphene point electrode and a second graphene point electrode on the graphene array electrode, and performing oxygen plasma etching on the first graphene point electrode and the second graphene point electrode to obtain a graphene nanogap point electrode pair;

[0054] S400, placing the graphene nanogap point electrode pair and the tetraligand dipole compound in a reaction system, allowing the single tetraligand dipole molecule to self-assemble with the graphene nanogap point electrode pair, and obtaining a probabilistic bit device based on the dipole moment of the single tetraligand molecule.

[0055] In the following examples, the experimental methods used are conventional methods unless otherwise specified, and are carried out according to the techniques or conditions described in the literature in this field or according to the product instructions. The materials, reagents, etc. used are all commercially available unless otherwise specified.

[0056] Example 1

[0057] Compound II 、

[0058] Compound III 、

[0059] Compound IV Preparation.

[0060] 1. Preparation of Compound Ⅰ , the process is as follows:

[0061] Under argon atmosphere, at room temperature, slowly add compound (40mmol, 5g), ethanol aqueous solution (100ml) and ferric chloride (FeCl3·6H2O) (15mmol, 4g) with a volume ratio of 1:1, and continued stirring for 12h. Then, the pH was adjusted with a 1mol / L NaOH aqueous solution until a solid precipitated, and the solid was filtered to obtain compound I. The crude product was purified by silica gel column chromatography (eluting solvent was a mixed solvent of dichloromethane and methanol, volume ratio was 9:1), and recrystallized from ethanol to obtain the purified black-red solid compound I. ;

[0062] ¹H NMR (400 MHz, DMSO-d6) δ (ppm) of compound Ⅰ: 8.50 (d, 4H, J = 6.0 Hz), 7.10 (d, 4H, J = 6.0 Hz), 3.15 (t, 4H, J = 6.5 Hz), 2.80 (s, 4H), 65 (t, 4H, J = 6.5 Hz), 1.50 (s, 4H);

[0063] ¹³C NMR (100 MHz, DMSO-d6) δ (ppm): 150.5, 123.8, 142.0, 39.2, 32.4, 28.0 of compound I;

[0064] Compound Ⅰ (TOF-ESI+) (m / z): C 16 H 22 N4270.18.

[0065] 2. Preparation of Compound II , the process is as follows:

[0066] Dissolve 1 mmol of CuSO4·5H2O (about 0.25 g) in 20 mL of deionized water and stir until completely dissolved to obtain a blue copper sulfate solution.

[0067] Compound I (2 mmol, 0.54 g) was added to 20 mL of a water-ethanol mixed solvent (volume ratio of 1:1) and dissolved. Sodium benzenesulfonate (2 mmol, 0.44 g) was then added and mixed uniformly to obtain a sodium benzenesulfonate solution. The solution was slowly added to the copper sulfate solution prepared above while stirring and maintaining the temperature at about 50°C. The pH of the reaction solution was adjusted to about 7.5 with a 1 wt% NaOH aqueous solution (weakly alkaline conditions promote coordination). The reaction was continued with stirring for about 5 h. When the color of the reaction solution changed from blue to dark blue or green, stirring was stopped. The reaction solution was cooled to room temperature, 10 mL of ethanol was added to reduce the solubility, the solution was allowed to stand for 12 h, and filtered to obtain a precipitate. The precipitate was washed with cold ethanol and ether in sequence, and vacuum dried to obtain a light blue powder. The light blue powder was purified by silica gel column chromatography (eluting solvent was a mixed solvent of dichloromethane and methanol, volume ratio of 9:1). After recrystallization from ethanol, purified compound II was obtained. ;

[0068] ¹H NMR (400 MHz, DMSO-d6) δ (ppm) of compound II: 8.55 (br, 4H), 7.30 (br, 4H), 3.25 (br, 4H), 2.80 (br, 4H), 2.75 (br, 4H), 1.55 (br, 4H);

[0069] ¹³C NMR (100 MHz, DMSO-d6) δ (ppm): 152.0, 124.5, 140.8, 40.1, 33.6, 28.5;

[0070] Compound II (TOF-ESI+) (m / z): C 16 H 26 CuN4O6S2497.06.

[0071] 3. Preparation of Compound III , the process is as follows:

[0072] Dissolve 1 mmol of CuSO4·5H2O (about 0.25 g) in 20 mL of deionized water and stir until completely dissolved to obtain a blue copper sulfate solution;

[0073] Compound I (2 mmol, 0.54 g) was added to 20 mL of a water-ethanol mixed solvent (volume ratio of 1:1) and dissolved. Dimethyl sulfoxide (2 mmol, 0.25 ml) was added and stirred to dissolve to obtain a solution. The solution was slowly added to the copper sulfate solution prepared above while stirring and maintaining the temperature at about 50°C. The pH of the reaction solution was adjusted to about 7.5 with a 1 wt% NaOH aqueous solution (weakly alkaline conditions promote coordination). The reaction was continued with stirring for about 5 h. When the color of the reaction solution changed from blue to dark blue or green, stirring was stopped. The reaction solution was cooled to room temperature, 10 mL of ethanol was added to reduce the solubility, the solution was allowed to stand for 12 h, and filtered to obtain a precipitate. The precipitate was washed with cold ethanol and ether in sequence, and vacuum dried to obtain a light blue powder. The light blue powder was purified by silica gel column chromatography (eluting solvent was a mixed solvent of dichloromethane and methanol, volume ratio of 9:1). After recrystallization from ethanol, the purified compound III was obtained. ;

[0074] ¹H NMR (400 MHz, DMSO-d6) δ (ppm) of compound III: 8.59 (br, 4H), 7.39 (br, 4H), 3.55 (br, 4H), 2.83 (br, 4H), 2.65 (br, 4H), 1.47 (br, 4H);

[0075] ¹³C NMR (100 MHz, DMSO-d6) δ (ppm): 158.0, 125.5, 143.8, 40.1, 33.8, 29.5 of compound III;

[0076] Compound III (TOF-ESI+) (m / z): C 16 H 24 CuN4O2S2431.06.

[0077] 4. Preparation of Compound IV , the process is as follows:

[0078] Dissolve 1 mmol of CuSO4·5H2O (about 0.25 g) in 20 mL of deionized water and stir until completely dissolved to obtain a blue copper sulfate solution;

[0079] Compound I (2 mmol, 0.54 g) was dissolved in 20 mL of a water-ethanol mixed solvent (volume ratio 1:1), and then (2mmol, 0.3ml), after mixing evenly, a solution was obtained, which was slowly added to the copper sulfate solution prepared above, while stirring and maintaining the temperature at about 50°C, and the pH of the reaction solution was adjusted to about 7.5 with a 1wt% NaOH aqueous solution (weakly alkaline conditions promote coordination). The reaction was continued with stirring for about 5h. When the color of the reaction solution changed from blue to dark blue or green, stirring was stopped, the reaction solution was cooled to room temperature, 10mL of ethanol was added to reduce the solubility, and the solution was allowed to stand for 12h. The solution was filtered to obtain a precipitate, which was washed with cold ethanol and ether in turn, and dried in vacuo to obtain a light blue powder. The light blue powder was purified by silica gel column chromatography (the elution solvent was a mixed solvent of dichloromethane and methanol in a volume ratio of 9:1), and recrystallized from ethanol to obtain the purified compound IV. ;

[0080] ¹H NMR (400 MHz, DMSO-d6) δ (ppm) of compound IV: 8.58 (br, 4H), 7.39 (br, 4H), 3.45 (br, 4H), 2.82 (br, 4H), 2.35 (br, 4H), 1.52 (br, 4H);

[0081] ¹³C NMR (100 MHz, DMSO-d6) δ (ppm): 152.0, 128.5, 143.8, 40.1, 38.6, 28.5;

[0082] Compound IV (TOF-ESI+) (m / z): C 20 H 24 CuF6N4O4561.10.

[0083] Example 2

[0084] The process of preparing a probabilistic bit device based on the dipole moment of a single tetraligand molecule is as follows:

[0085] A single layer of graphene was deposited on copper foil using chemical vapor deposition. The single layer of graphene was then attached to a clean quartz wafer using scotch tape. Polymethyl methacrylate (PMMA) was then spin-coated on the single layer of graphene using a spin coater at 4000 rpm for 40 seconds. The coating was then baked on a heating plate at 180°C for 2 minutes. The excess PMMA and graphene on the back of the copper foil were then etched away using oxygen plasma to obtain a PMMA-single layer of graphene-copper foil structure.

[0086] The PMMA-single-layer graphene-copper foil was cut into 1 cm × 1 cm small pieces, placed in a saturated ferric chloride solution, and the copper foil on the back was dissolved to obtain a PMMA-supported single-layer graphene film.

[0087] The PMMA-supported single-layer graphene film was soaked in hydrochloric acid solution, aqueous solution and potassium hydroxide solution, and then transferred to a silicon wafer covered with 350 nm thick silicon oxide. The film was allowed to stand, dried, and the PMMA was removed using acetone under heating conditions at 120°C to obtain a graphene-silicon wafer layer.

[0088] Mark the graphene-silicon wafer layer, spin-coat photoresist on the marked large graphene, and use a strip mask to photoetch the graphene strips. After exposure and development, the strip-shaped photoresist is left to protect part of the graphene, while the rest of the graphene is exposed. The exposed graphene is removed by oxygen plasma etching; then the photoresist is also removed by soaking in acetone to obtain a backing with a central graphene strip.

[0089] Electrodes were photolithographically formed on the graphene strips on the backing, followed by evaporation of 8nm of chromium and 60nm of gold to create a graphene strip with gold electrodes. The photoresist was then removed by soaking in acetone, resulting in a graphene array electrode. The conductivity of the graphene array electrode was tested at 50mV, and backings with conductivity in the 10μA range were selected for subsequent experiments.

[0090] A dotted line with a length of 150 nm and a width of 5 nm was etched on the graphene array electrode by electron beam exposure to obtain a first graphene point electrode and a second graphene point electrode.

[0091] The first graphene point electrode and the second graphene point electrode are etched with oxygen plasma, and each pair of electrodes is tested for continuity using a probe station and a source meter. After repeating this step multiple times, a graphene nanogap point electrode pair is obtained.

[0092] The graphene nanogap point electrode pair was placed in a two-necked flask. 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (5 mL) and a pyridine solution of a tetraligand dipole compound were added to the flask. The concentration of the solution was not less than 0.5 mM. The mixture was reacted in a nitrogen atmosphere for 48 h, so that the -NH2 at both ends of the bottom of the tetraligand dipole molecule formed amide covalent bonds with the -COOH at the end of the graphene nanogap point electrode pair. The device was removed from the two-necked flask, washed three times with deionized water and acetone, respectively, and the surface was blown dry with nitrogen for later use. This yielded a probabilistic bit device based on the dipole moment of a single tetraligand molecule.

[0093] Among them, the tetracoordinate dipolar compound is compound III When , the test results of the probability bit device are as follows Figure 2 and Figure 3 As shown;

[0094] The tetraligand dipolar compound is selected from compound II When , the test results of the probability bit device are as follows Figure 4 and Figure 5 As shown;

[0095] The tetraligand dipolar compound is selected from compound IV When , the test results of the probability bit device are as follows Figure 6 and Figure 7 As shown;

[0096] from Figure 2 、 Figure 4 and Figure 6 It can be seen that the tetracoordinate dipole molecule is successfully connected between the graphene nanogap point electrodes, and the molecular probabilistic bit device can be controlled by the bias voltage parameter. The molecular conductance fluctuates between two values, and the two conductance states of the molecule form a stable probability ratio over a long time scale.

[0097] in, Figure 2 Figure A shows the current changes in the time range of 0 to 200 seconds. As can be seen from the figure, the current value fluctuates between 6 and 11 nA, showing dense and frequent current changes; Figure 2 Figure B is a partial enlargement of Figure A, showing the current changes in the time range of 21s to 25s. It can be seen that the current has obvious drops and increases at certain moments, which may be related to the electrochemical blockade mode; Figure 2 Figure C shows the current change at a voltage of 0.45 V. In the time range of 0 to 1000 ms, the current value is between 7 and 10 nA, and there is an obvious current decrease process, which may be related to the quantum dot tunneling effect.

[0098] Figure 4Figure A shows the current changes in the time range of 0 to 200 seconds. As can be seen from the figure, the current value fluctuates between 4.5nA and 8.0nA. The overall trend is relatively stable, but there are some small fluctuations and changes. Figure 4 Figure B is a partial enlargement of Figure A, showing the current changes in the time range of 20s to 25s. The current value rises and falls significantly in a short period of time, showing a pulse-like characteristic, indicating that the current changes significantly within a specific time period. Figure 4 Figure C shows the current change at a voltage of 0.45V. The time range is from 0 to 1800ms. The current value fluctuates around 5.0nA and is relatively stable overall. However, there is a clear upward trend in the early stage, and then it tends to be stable.

[0099] Figure 6 Figure A shows the current changes in the time range of 0 to 200 seconds. As can be seen from the figure, the current value fluctuates between 7nA and 13nA. The overall trend is relatively stable, but there are some sharp current drops and increases, indicating that there may be transient changes in conductance or impedance. Figure 6 Figure B is a partial enlargement of Figure A, showing the current changes in the time range of 105s to 110s. It can be seen that the current has obvious drops and rises in a short period of time, which may be related to the single-molecule conductance or quantum dot tunneling effect. Figure 6 Figure C shows the current change at a voltage of 0.45V. In the time range of 0 to 1000ms, the current value fluctuates around 5.0nA, which is relatively stable overall. However, there is an obvious upward trend in the early stage, and then it tends to be stable.

[0100] from Figure 3 It can be seen that in the process of reducing the bias voltage from 0.5V to 0.3V, the proportion of the high conductivity state of a single tetraligand dipole molecule decreased from 90% to less than 10%, and the proportion of the low conductivity state increased from less than 10% to 91%. Between approximately 0.45V and 0.4V, the two states of a single tetraligand dipole molecule accounted for roughly the same proportion, 50% each, realizing the function of adjustable probability bit.

[0101] from Figure 5 It can be seen that in the process of reducing the bias voltage from 0.55V to 0.1V, the proportion of the low conductivity state of a single tetraligand dipole molecule decreased from 92% to less than 10%, and the proportion of the high conductivity state increased from less than 10% to more than 93%. At about 0.45V, the two states of a single tetraligand dipole molecule accounted for roughly the same proportion, 50% each, realizing the function of adjustable probability bit.

[0102] from Figure 7It can be seen that in the process of reducing the bias voltage from 0.6V to 0.1V, the proportion of the low conductivity state of a single tetraligand dipole molecule decreased from 92% to less than 10%, and the proportion of the low conductivity state increased from less than 10% to 93%. At about 0.5V, the two states of a single tetraligand dipole molecule accounted for roughly the same proportion, 50% each, realizing the function of adjustable probability bit.

[0103] There are many reasons why changes in the dipole moment of a single tetraligand molecule induce changes in conductivity. These include: regulating electron transport properties by altering the charge distribution and local electric field within the molecule; influencing the contact potential and interface effects between the molecule and the metal electrode; changing the molecule's energy level structure and energy gap, thereby affecting electron injection and transport capabilities; and further regulating conductivity by influencing electron tunneling and electron interactions. In a probabilistic bit device based on the dipole moment of a single tetraligand molecule, the probability of the two states varies under different bias voltages. This is primarily due to factors such as the bias voltage altering the energy level structure of the electrons within the molecule, the electron injection and tunneling processes, the interaction between the molecular dipole moment and the electric field, and thermal effects. By influencing electron transport and the relative positions of energy levels within the molecule, the bias voltage alters the relative probability distribution between the two states.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A probabilistic bit device based on the dipole moment of a single tetraligand molecule, characterized in that: The invention comprises a first graphene point electrode, a molecular bridge and a second graphene point electrode connected in sequence, wherein the first graphene point electrode and the second graphene point electrode form a graphene point electrode pair, the molecular bridge is respectively connected to the first graphene point electrode and the second graphene point electrode via an amide bond, and the molecular bridge serves as a functional unit for probability bit regulation; The molecular bridge is selected from a single tetraligand dipole molecule, and the single tetraligand dipole molecule is selected from any one of the following structural formulas: 、 、 。 2. The probabilistic bit device based on a single tetraligand molecular dipole moment according to claim 1, wherein: The first graphene point electrode and the second graphene point electrode are nanogap point electrodes.

3. The probabilistic bit device based on a single tetraligand molecular dipole moment according to claim 1, wherein: It also includes a first metal electrode and a second metal electrode, the first metal electrode is evaporated on the first graphene point electrode, the second metal electrode is evaporated on the second graphene point electrode, and the first metal electrode and the second metal electrode form a metal electrode pair.

4. The probabilistic bit device based on a single tetraligand molecular dipole moment according to claim 3, characterized in that: The first metal electrode and the second metal electrode are selected from gold electrodes.

5. The probabilistic bit device based on a single tetraligand molecular dipole moment according to claim 3, characterized in that: It also includes a protective layer, which covers the metal electrode pair and the graphene point electrode pair.

6. The probabilistic bit device based on a single tetraligand molecular dipole moment according to claim 5, characterized in that: The protective layer is made of hexagonal boron nitride.

7. A method for preparing a probabilistic bit device based on the dipole moment of a single tetraligand molecule, characterized in that: The method for preparing a probabilistic bit device based on a single tetraligand molecular dipole moment as claimed in any one of claims 1 to 6 comprises the following steps: S100, preparing a single layer of graphene on a backing by using a chemical vapor deposition method and an oxygen plasma etching method; S200, preparing a graphene array electrode on the single-layer graphene by using photolithography technology and peroxide plasma etching technology; S300, using electron beam exposure and etching technology to prepare a first graphene point electrode and a second graphene point electrode on the graphene array electrode, and performing oxygen plasma etching on the first graphene point electrode and the second graphene point electrode to obtain a graphene nanogap point electrode pair; S400, placing the graphene nanogap point electrode pair and the tetraligand dipole compound in a reaction system, allowing the single tetraligand dipole molecule to self-assemble with the graphene nanogap point electrode pair, and obtaining a probabilistic bit device based on the dipole moment of the single tetraligand molecule.

8. The method for preparing a probabilistic bit device based on a single tetraligand molecular dipole moment according to claim 7, wherein: In step S400 , the reaction system includes a catalyst and a reaction solvent, the catalyst is selected from 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, and the reaction solvent is selected from pyridine.

9. The method for preparing a probabilistic bit device based on a single tetraligand molecular dipole moment according to claim 8, wherein: The concentration of the tetraligand dipole compound in the reaction system is ≥0.5 mM.

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