Method for suppressing signal by increasing entropy and quantum algorithm

Abstract

A method of suppressing a signal by increasing entropy in a system includes iteratively applying a set of electromagnetic (EM) pulses to the system, the set of EM pulses causing exchange between pairs of system levels: a first system level in which a reset system is at a highest level and a target system is at a lowest target system level; the reset system is at the highest energy level and the target system is at the highest target system energy level; waiting for a period of time. This will suppress the signal of the target element. This may be, for example, a solvent signal in the NMR.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 342,138, filed on May 15, 2023, the contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a method for suppressing elemental signals in a quantum system by increasing entropy. Background Art

[0004] Quantum technologies are advancing at an unprecedented pace. What is now being called the “second quantum revolution” is changing the face of modern technology, from communications to computing and sensing (see www.nist.gov / topics / physics / introduction-new-quantum-revolution / second-quantum-revolution).

[0005] One of the main challenges limiting the real-life application of quantum technology is that it is extremely difficult to separate the elements of interest in a quantum system from its environment. Quantum systems are often complex and may involve too many unwanted elements for practical applications.

[0006] Different techniques have been developed to isolate the evolution of quantum elements of interest and protect them from their interaction with the environment. However, for measurements, these unwanted elements may still produce signals that can obscure the desired signal from the element of interest and in a sense reduce the resolution.

[0007] For example, in spin systems, one has used techniques such as error correction, dynamical decoupling, and recombination pulses to preserve the spin state. But for measurements, one still gets signals from unwanted spins in the system. These measurements are often spectroscopic, which can easily become complex for large systems. For example, for nuclear magnetic resonance (NMR) of large molecules, the spectrum often involves too many overlapping peaks, each arising from an element or spin in the molecule. However, one is usually only interested in a few elements or a subset of the peaks.

[0008] The same problem was explored in NMR spectroscopy before the advent of quantum technology. For example, for liquid NMR, different ideas were proposed to suppress the signal of the solvent.

[0009] Similarly, for magnetic resonance imaging (MRI), it makes sense to turn off the signal of specific molecules while keeping the signal of other molecules intact. This is very important for the specificity of the scan. Summary of the invention

[0010] The present disclosure describes a method for suppressing the signal of certain target elements in a quantum system by increasing the entropy of the target elements. The disclosed method is state-independent, making it practical for practical applications.

[0011] In one aspect, a method for increasing entropy in a system is provided, the system comprising a target system having two energy states and a first relaxation time, and a reset system having two different energy states and a second relaxation time shorter than the first relaxation time, the system having a set of system energy levels, the set of system energy levels comprising possible combinations of target system energy levels and reset system energy levels, the method comprising: iteratively applying a set of electromagnetic (EM) pulses to the system to effect an exchange between: a) a first system energy level, wherein the reset system is at a highest energy level (i.e., a reset excited state) in the set of reset system energy levels, and the target system is at a lowest target system energy level (i.e., a target ground state); b) a corresponding second system energy level, wherein the reset system is at a highest energy level (i.e., a reset excited state) in the set of reset system energy levels, and the target system is at a highest target system energy level (i.e., a target excited state); and waiting for a time period, the time period being of the order of the second relaxation time and shorter than the first relaxation time, to cause at least some reset elements of the reset system to reset from the highest energy state.

[0012] In one embodiment, the target system includes one or more target elements, each target element has a first relaxation time, and the target system also has a set of target system energy levels; the reset system includes one or more reset elements, each reset element has a second relaxation time shorter than the first relaxation time, and the reset system also includes a set of reset system energy levels; the system includes a set of system energy levels, which includes all possible combinations of target system energy levels and reset system energy levels.

[0013] In another aspect, a computer-readable medium is provided that includes computer-executable instructions that, when executed, cause a computing device to perform the method.

[0014] In yet another aspect, a computing device is provided, comprising a processor and a memory, the memory comprising computer executable instructions which, when executed by the processor, cause the device to perform the method. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Exemplary embodiments will now be described with reference to the accompanying drawings, in which:

[0016] Figure 1 is a schematic diagram illustrating energy levels of a target system and a reset system and a process of increasing entropy in the system in one iteration according to an embodiment;

[0017] Figure 2 for Figure 1An exemplary circuit diagram for implementing the entropy increase method in the illustrated embodiment;

[0018] Figure 3 is a schematic diagram showing the process that occurs in each iteration;

[0019] Figure 4 It shows that according to Figure 1 The embodiments shown and Figure 2 A flow chart of a method for increasing entropy in a system of circuits;

[0020] Figure 5 It shows that according to Figure 1 The embodiments shown and Figure 2 Computer simulation of the signal (i.e. polarization) changes of the target element of the circuit shown;

[0021] Figure 6 is based on Figure 1 The embodiments shown and Figure 2 The circuit shows Figure 4 Computer simulation of the convergence rate of the process in;

[0022] Figure 7 shows the chemical structure of acetic acid; and

[0023] Figure 8 An example configuration of a device for implementing the processes described herein is shown. DETAILED DESCRIPTION

[0024] In quantum systems, it is recognized that it would be advantageous to be able to switch off the elements of the system that are not needed for measurement and focus only on the elements that are relevant to our application.

[0025] The present disclosure proposes a method to achieve this by providing a technique to suppress the signal of any element in a quantum system (e.g., an element in a molecule or a qubit in a quantum computer) by increasing the entropy of the unwanted element. This is in contrast to previous methods for reducing entropy in quantum systems (see U.S. Pat. No. 10,560,096, which is incorporated herein by reference).

[0026] That is, this disclosure describes a method of increasing the entropy of a quantum system, which can be used to suppress the signals of unwanted elements in the system.

[0027] The disclosed method is state-independent and therefore has practical applicability in practical applications. This means that the currently disclosed method is not affected by defects that affect the state of the system in the process.

[0028] For simplicity and clarity of description, reference numerals may be repeatedly used in the drawings to indicate corresponding or similar elements. Many details are set forth to provide an understanding of the embodiments described herein. These embodiments may be implemented without these details. In other cases, well-known methods, procedures, and components are not described in detail to avoid obscuring the embodiments.

[0029] As used in this disclosure, a "quantum system" (also referred to herein simply as a "system") refers to a physical system with discrete energy levels (referred to as system energy levels). Quantum systems include systems that are considered classical or quasi-classical, such as NMR samples.

[0030] The system includes a target system and a reset system. The target system is to suppress element signals. The target system includes one or more target elements, and the reset system includes one or more reset elements, wherein the relaxation time of the reset element is shorter than the relaxation time of the target element. Typically, the relaxation time of the reset element may be an order of magnitude shorter than the relaxation time of the target element. However, in some applications, the relaxation time of the reset element may be one-third or other fraction of the relaxation time of the target element, depending on the implementation settings and the desired final accuracy. The target element and the reset element can be of any size, such as a spin 1 / 2 particle, or a multi-level quantum system. A multi-level quantum system includes elements having more than two states or energy levels. A multi-level quantum system can include, for example, a spin 1 particle and a nitrogen vacancy (NV) center.

[0031] The target system has multiple target system energy levels, and the reset system includes multiple reset system energy levels. For example, when the target element and the reset element include non-zero spin particles, placing the system in a magnetic field will cause the different states of the target system and the reset system to be split into multiple target system energy levels and multiple reset system energy levels, respectively. Each state of the system has an associated system energy level. Similarly, each target system state and reset system state has an associated target system energy level and an associated reset system energy level, respectively. In the present disclosure, "state" and "energy level" can be used interchangeably.

[0032] refer to Figure 1 , provides a schematic diagram showing various energy levels of the target and reset system 100. The arrows on each axis represent increasing energy, such that Figure 1 The energy levels near the bottom are lower in energy than those shown above for resetting the system. Figure 1 The energy levels near the left side indicate that the target system has lower energy levels than those shown on the right side. Figure 1The notation used in denotes the ground state or lowest energy level |0>, followed by the excited state or highest energy level |1>. The combination of all possible target system energy levels and reset system energy levels gives all possible system energy levels for the entire system.

[0033] A method for increasing entropy in a system by iteratively performing a set of predetermined permutation operations on pairs of energy states of the system is disclosed. The set of permutation operations may be performed in the system by applying a set of electromagnetic (EM) pulses to the system.

[0034] For simplicity, we describe the method for a target element containing two energy states and a reset element containing two energy states. For example, this might include a spin 1 / 2 particle or qubit as the target or reset system.

[0035] As shown below, if the state of the reset element flips / changes only when the target element is in a higher energy state, the entropy converges to a maximum value.

[0036] This can also be described as an exchange operation performed between a pair of energy states, which include a first system energy level, in which the reset system is at the highest energy level of the reset system energy level group and the target system is at the highest energy level of the target system energy level group, and a corresponding second quantum system energy level, in which the reset system is at the highest energy level of the reset system energy level group and the target system is at the lowest energy level of the target system energy level group.

[0037] The EM pulses that affect such permutation operations can be determined based on the energy difference between each pair of system energy levels, which energy difference can be determined, for example, by spectroscopy performed on the system. For example, each permutation operation can have a corresponding EM pulse whose frequency corresponds to the energy difference of the energy levels exchanged by the permutation operation. In other examples, the permutation operation can be associated with multiple EM pulses (or "pulse trains") such that the permutation operation is performed through one or more intermediate states of the system energy levels, with the end result being the desired permutation operation between the desired pair of system energy levels. The applied EM pulses can be π pulses.

[0038] The number of times or iterations that a set of EM pulses are applied in order to achieve convergence can be determined by, for example, the desired accuracy and precision of the operation. The number of iterations can be a predetermined number of iterations that is related to the number of iterations at which the system is predicted to reach a desired fidelity or the amount by which the system deviates from the ideal state is less than or equal to a predetermined amount. Alternatively, or in addition, the system can be monitored such that a set of EM pulses is applied until it is determined that the system has reached the desired fidelity or the amount by which the system deviates from the ideal state is less than or equal to a predetermined amount. The ideal state can be a maximum mixing state (MMS).

[0039] The whole process consists of many iterations and can be described by a time homogeneous Markov process. In the following description, the transfer matrix of the process is found and the spectrum of the transfer matrix is ​​calculated. The spectrum is then used to show that applying the transfer matrix to the system converges to the MMS and to provide an upper bound on the number of iterations that lead to convergence.

[0040] The following description of the disclosed technology utilizes a system comprising two elements or qubits, wherein a first element or qubit forms a target system and a second element or qubit forms a reset system, ie, a reset qubit.

[0041] The heating operation entangles the states of the target and reset systems. After the heating operation, the reset system interacts with the heat bath, resulting in the loss of information transferred from the target system to the reset system. This increases the entropy of the target system.

[0042] Mathematically speaking, the reset step can be described as where Tr R is the partial trace of the reset element, ρ T,R is the density matrix describing the quantum state of the target element, and ρR is the density matrix of the reset system, which can be given by the following formula:

[0043]

[0044] Where z = (e ∈ +e -∈ ). The parameter ∈ is called polarization, δ is the energy gap between the reset element states, K b is the Boltzmann constant and T B Bath temperature.

[0045] You can also use ρ T To refer to the state of the target element or qubit. Typically, the subscript R refers to the reset element or qubit and T refers to the target element or qubit.

[0046] The heating operation is given by a unitary operation on two qubits of the target and reset elements. Assume that the structure of the Hilbert space is That is, the first part is the target element and the second part is the reset element.

[0047] In the techniques described in this disclosure, the following unitary operations may be applied in each iteration:

[0048]

[0049] This matrix is ​​known as a CNOT operation, which uses the reset element as a control bit and flips / changes the state of the target only when the reset element is in the highest energy (excited) state.

[0050] The method involves repeating a fixed number of iterations.

[0051] Each iteration consists of first resetting the reset element and then CNOT Applies to the entire system.

[0052] Now refer to the attached Figure 2 , shows a schematic diagram of a quantum circuit corresponding to a single iterative process. Each row in process 200 represents a spin or qubit, the first row is the target spin or qubit, and the second row represents a reset. Process 200 begins with CNOT gate 210, followed by reset 220. CNOT quantum gate 210 uses the second spin or qubit as a control bit to operate on the target spin or qubit.

[0053] Mathematically speaking, each iteration applies the following operation (or quantum pass) to the full density matrix:

[0054] Note that starting from a hot / equilibrium state, this process keeps the density matrix diagonal for the entire system.

[0055] Similarly, starting from any diagonal state of the density matrix of the complete system, the process keeps the system density matrix diagonal.

[0056] This means that the diagonal elements of the density matrix can provide a more compact representation of the quantum state. In t iterations, the diagonal elements of the whole system can be used to t}=Diag(ρ T,R ), in t iterations, the diagonal elements of the target system can be treated as {p t}=Diag(ρ T ).

[0057] The process is independent of the iteration or the state of the target and reset elements, resulting in a time-homogeneous Markov process. The sequence of elements on the diagonal of the density matrix forms a Markov chain. {p t} represents the tth link of the chain of the target element state. Each link is a vector with two elements.

[0058] refer to Figure 3 , a schematic diagram 300 is shown illustrating the process that occurs during each iteration. The process 300 starts from the sequence {p t} That is, 310, which is the diagonal element of the density matrix of the target element. Specifically, in the vector , α gives the probability that the target element is in the ground state (the target energy state with lower energy), and β gives the probability that the target element is in the excited state (the target energy state with higher energy). This gives a complete state 320, which is a combined state of the energy states of the target element and the reset element after reset, represented by {λ t}. Note that CNOT, which acts on both the target and reset elements, requires the complete state of the system. Next, the operation U CNOT Applied to the state, that is, 330. As shown in 330, U CNOT Exchange {λ t} and make {λ t The first and third elements of} remain unchanged. The result of applying the operation is represented by {ξ t} indicates. After CNOT, the reset element is reset, which causes the state in 340 to become the final state of the target element after iteration. The iteration ends. 340 shows the simplified state of the target element of the new iteration, that is, {p t+1}. This is equivalent to ρ T =Tr R (ρ T,R ). The first element of the target state is the complete system state from 330, namely {ξ t}, while the second element of the target state is the complete system state from 330, namely {ξ t} is the sum of the last two elements of .

[0059] For simplicity, we can focus on the target element or qubit and keep track of the reset qubits, which means calculating the total probability of the qubit state of that system by summing over all possible corresponding reset qubit states. The result of keeping track of the reset qubits is the following update rule for the diagonal elements of the target element:

[0060]

[0061] This update rule provides the following transition matrix for the Markov process:

[0062]

[0063] It can be verified that t+1}=T.{p t} is the update rule in Formula 2.

[0064] The spectrum of the transfer matrix can be used to prove that the Markov chain converges to MMS. T has two eigenvalues, one of which is λ1=1 and the other is λ2=tanh∈. It is easy to prove that |λ2|≤1. The eigenstate corresponding to eigenvalue one is:

[0065]

[0066] It is equal to MMS. Because the magnitude of the other eigenvalue is less than 1, that is, |λ2|≤1, the Markov chain converges asymptotically to {p ∞}.

[0067] Therefore, in the above process, the same set of permutation operations is iteratively applied to the system, and then the reset elements are reset, so that the system converges to the MMS in a manner independent of the state of the system in any iteration.

[0068] Reference now Figure 4 , a flow chart of a method for increasing entropy in a system is shown. The method may be performed by software, for example, Figure 8 The computer readable storage medium 804, such as a non-volatile computer readable medium, may be configured to apply or initiate application of an EM pulse 806, such as, for example, by an EM pulse generator 808, as described herein.

[0069] At 410, a set of predetermined EM pulses are applied to the system to achieve an exchange between predetermined energy level pairs of the system. As described above, the system includes a target system including one or more target elements and a reset system including one or more reset elements. The relaxation time of the reset element is shorter than the relaxation time of the target element. The target element and the reset element can be, for example, any one of spin 1 / 2 particles, or a multi-level quantum system including, for example, electrons, spin 1 particles, and nitrogen vacancy (nv) centers.

[0070] The target system has multiple target system energy levels, and the reset system includes multiple reset system energy levels. The combination of all possible target system energy levels and reset system energy levels gives all possible system energy levels of the entire system.

[0071] The predetermined EM pulse group realizes the exchange operation between pairs of system energy levels, each pair of energy levels includes a first quantum system energy level, in which the reset system is at the highest reset system energy level, that is, the reset system is in an excited state, and the target system is at the lowest target system energy level, that is, the target system is in the ground state, and a corresponding second quantum system energy level, in which the reset system is at the highest reset system energy level, and the target system is at the highest target system energy level, that is, the target system is in an excited state.

[0072] As previously described, the frequency of the EM pulses that effect such an exchange operation can be determined based on the energy difference between the system energy levels between the states corresponding to the exchange. The energy difference associated with each pair of system energy levels can be determined, for example, by spectroscopic measurements performed on the system. Each exchange operation can be associated with one EM pulse in the pulse group, or with multiple EM pulses. For example, multiple EM pulses can be applied so that the exchange operation is achieved through an intermediate system energy level. In addition, since the EM pulses are determined based on the energy difference between the states corresponding to the exchange, a single EM pulse may be associated with multiple pairs of system energy levels if the energy differences between multiple pairs of system energy levels are the same. The EM pulses may be π pulses.

[0073] The set of EM pulses applied at 410 may be applied simultaneously or sequentially, or a portion may be applied simultaneously and another portion may be applied sequentially.

[0074] After applying the predetermined set of EM pulses at 410, a time period elapses at 420 to cause at least some of the reset elements to reset from the highest reset system energy level to a lower reset system energy level. The elapsed time period may be approximately the same as the relaxation time of the reset system, which is much shorter than the relaxation time of the target system. In this way, the reset elements are reset between iterations of applying the set of EM pulses, while the target elements do not have time to reset substantially.

[0075] In some embodiments, the relaxation time of the reset system can be an effective relaxation time that is shorter than the intrinsic relaxation time of the reset system. The effective relaxation time can be the result of operating the reset system to shorten the relaxation time from the intrinsic relaxation time to the effective relaxation time. For example, operating the reset system can include performing, for example, photopolarization, photoexcitation, or dynamic nuclear polarization during the time period elapsed at 420.

[0076] At 430, it is determined whether a stop condition is met. The stop condition may be, for example, a predetermined number of iterations. In another example, the stop condition may be that the system reaches a certain state. For example, reaching a MMS near state or after a certain time. The near state may be determined by the accuracy and quality of the EM pulses and other factors that may affect the fidelity of the state.

[0077] If it is determined at 430 that the stop condition is not met, the process returns to 410 and the predetermined set of EM pulses is applied again, followed by a wait period at 420. If it is determined at 430 that the stop condition is met, the process ends.

[0078] Figure 5 Shows from The simulation results of the above process are shown for the target system (i.e., fully polarized or pure state) at the beginning. The y-axis represents {p t}, i.e., the difference between the probabilities of the ground and excited states of the target element. The x-axis represents the number of iterations. The plot shows that the process converges to the target state where the probabilities of the two energy states (ground and excited) are equal, i.e., MMS. Note that MMS is the desired output of the process because the target element does not produce any signal when it is in the MMS state. 410 is the same plot shown on a logarithmic scale. This shows that the method converges exponentially faster.

[0079] Figure 6 The relationship between the convergence speed and the reset polarization is shown. The results show that the higher the reset polarization, the slower the convergence speed. This suggests that reset elements with lower reset polarization are more effective for the heating process.

[0080] Embodiments of the present disclosure provide a method of increasing entropy in a system having a target system and a reset system in a manner independent of the system states. The method utilizes a predetermined set of EM pulses to implement permutation operations between pairs of system states. Each pair of system states includes a first quantum system energy state in which the reset system is at a highest reset system energy level and the target system is at a lowest target system energy, and a corresponding second quantum system energy level in which the reset system is at a highest reset system energy level and the target system is at a highest target system energy.

[0081] In the foregoing description, for the purpose of explanation, many details are set forth in order to provide a thorough understanding of the embodiments. However, those skilled in the art will appreciate that these specific details are not necessary. In other cases, well-known electrical structures and circuits are shown in block diagram form to avoid confusion. For example, no specific details are provided regarding whether the embodiments described herein are implemented as software programs, hardware circuits, firmware, or a combination thereof.

[0082] Embodiments of the present disclosure may be represented as a computer program product stored in a machine-readable medium (also referred to as a computer-readable medium, a processor-readable medium, or a computer-usable medium having a computer-readable program code). The machine-readable medium may be any suitable tangible, non-temporary medium, including a magnetic, optical, or electrical storage medium, including a floppy disk, a compact disk read-only memory (CD-ROM), a storage device (volatile or non-volatile), or a similar storage mechanism. The machine-readable medium may contain various instruction sets, code sequences, configuration information, or other data, which, when executed, cause the processor to perform the steps in the method according to the embodiments of the present disclosure. It will be appreciated by those of ordinary skill in the art that other instructions and operations required to implement the embodiments may also be stored on the machine-readable medium. The instructions stored on the machine-readable medium may be executed by a processor or other suitable processing device, and may be interfaced with a circuit to perform the tasks.

[0083] The following embodiments are intended to be exemplary only. Those skilled in the art may effect changes, modifications and variations to the particular embodiments without departing from the scope of the invention which is limited only by the appended claims.

[0084] Example I: Solvent Suppression in Liquid State NMR

[0085] For liquid-state NMR applications, the sample is dissolved in a solvent. The solvent generates its own signal that may interfere with the signal of the sample. The method described here can be used to suppress the signal.

[0086] As a specific example, let's consider acetic acid, one of the most commonly used solvents for liquid NMR. Acetic acid produces signals on both the proton channel and the carbon channel. Figure 7 The chemical structure of acetic acid is shown.

[0087] carbon( 13 C) and hydrogen ( 1 H) coupling. Each carbon or proton has two energy states, a lower energy level (ground state) and a higher energy level (excited state). Depending on the application, it may be necessary to remove the signal of carbon or hydrogen. Suppose you need to remove the carbon ( 13 C). In this case, the hydrogen ( 1 H) is set to reset, and the carbon ( 13 C)) is set as the target. After a few iterations, Carbon converges to a no-signal state.

[0088] Example II: Signal Suppression for MRI

[0089] For MRI, signals are usually collected from the spins of hydrogen nuclei. However, this is sometimes not specific enough because different molecules such as fat and water can produce overlapping signals.

[0090] The method of the present invention can suppress one of the signals without changing the other signal. For example, we can use carbon and hydrogen in fat as reset and target respectively, suppressing the fat signal while maintaining the water signal.

[0091] Example III: Signal Suppression in Quantum Devices

[0092] For some quantum technologies, such as superconducting circuits for quantum computers or nitrogen-vacancy centers for quantum sensing, there are unwanted elements, such as manufacturing defects or nuclear spins, that can create signals that interfere with the actual signal.

[0093] In this case, the method presented in this article can suppress the defect signal. The defect is considered as a target and the controllable element in the quantum system or device is used as a reset. Applying this method will weaken the defect signal.

[0094] appendix

[0095] The convergence rate is determined by λ1=1 and the second largest eigenvalue The gap can be limited to The upper limit of mixing time is

[0096]

[0097] where c is a constant. This gives an upper limit on the mixing time.

Claims

1. A method of increasing entropy in a system, wherein the system comprises: a target system having one or more target elements, Each target element has a first relaxation time, The target system also has a set of target system energy levels; as well as a reset system having one or more reset elements, Each resetting element has a second relaxation time shorter than the first relaxation time, The reset system also has a set of reset system energy levels; The entire system has a set of system energy levels, which includes all possible combinations of target system energy levels and reset system energy levels, The method includes: iteratively applying a set of EM pulses to the system to achieve a swap between: a) a first system energy level wherein the reset system of the system is at a highest energy level in a set of reset system energy levels and the target system of the system is at a lowest target system energy level in a set of target system energy levels; and b) a corresponding second system energy level wherein the reset system is at the highest energy level in the set of reset system energy levels and the target system is at the highest target system energy level in the set of target system energy levels; as well as Waiting for a period of time that is comparable to the second relaxation time of the resetting element and shorter than the first relaxation time of the target element to cause at least some of the resetting elements of the resetting system to reset from the highest energy level.

2. The method according to claim 1, characterized in that: The target system includes a plurality of target elements.

3. The method according to claim 1 or 2, characterized in that: The reset system includes a plurality of reset elements.

4. The method according to any one of claims 1 to 3, characterized in that: At least one target element is a spin.

5. The method according to claim 4, characterized in that Each target element is a multi-level quantum system.

6. The method according to claim 5, characterized in that The multi-level quantum system is one of a spin 1 particle and a nitrogen vacancy (nv) center.

7. The method according to any one of claims 1 to 3, characterized in that: At least one reset element is a spin.

8. The method according to claim 7, characterized in that Each reset element is a multi-level quantum system.

9. The method according to claim 8, characterized in that The multi-level quantum system is one of a spin 1 particle and a nitrogen vacancy (nv) center.

10. The method according to any one of claims 1 to 3, characterized in that: The target element and the reset element are both spins.

11. The method according to claim 10, characterized in that The target element is composed of a different spin species than the reset element.

12. The method according to any one of claims 1 to 11, characterized in that: One or both of the target element and the reset element are quantum bits.

13. The method according to any one of claims 1 to 12, characterized in that: A set of electromagnetic pulses is used to implement a series of quantum logic gates to achieve the exchange between the energy level pairs of the first quantum system and the corresponding energy level pairs of the second quantum system.

14. The method according to claim 13, characterized in that The quantum logic gate includes a CNOT quantum gate with a reset element as control.

15. The method according to any one of claims 1 to 14, characterized in that: The second relaxation time is an effective relaxation time shorter than an intrinsic relaxation time of the resetting element.

16. The method according to any one of claims 1 to 15, characterized in that: Each iteration further comprises operating a reset system during the waiting period to shorten the second relaxation time from the intrinsic relaxation time to the effective relaxation time.

17. The method according to claim 16, characterized in that Operating the resetting system includes performing one of photopolarization, photoexcitation, and dynamic nuclear polarization.

18. The method according to any one of claims 1 to 17, characterized in that: At least some pairs of the first system energy level and the corresponding second system energy level correspond to one of an entangled system state or an off-diagonal system state.

19. The method according to any one of claims 1 to 18, characterized in that: The method is applied to a signal suppression system.

20. The method according to any one of claims 1 to 18, characterized in that: The method is applied to a solvent suppression system.

21. A method for increasing entropy in a system, the method comprising: Repeatedly applying a set of electromagnetic (EM) pulses to the system to effectuate an exchange between: a) a first system energy level wherein a reset system of the system is at a highest energy level in a set of reset system energy levels and a target system of the system is at a lowest target system energy level in a set of target system energy levels; and b) a corresponding second system energy level wherein the reset system is at a highest energy level in a set of reset system energy levels and the target system is at a highest target system energy level in a set of target system energy levels; as well as Waiting for a time period that is comparable to the second relaxation time of the reset element and shorter than the first relaxation time of the target element to cause at least some of the reset elements of the reset system to reset from the highest energy level.

22. A computer-readable medium comprising computer-executable instructions which, when executed, cause a computing device to perform the method of any one of claims 1-21.

23. A computing device comprising a processor and a memory, the memory comprising computer executable instructions, which, when executed by the processor, cause the computing device to perform the method of any one of claims 1-21.

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