Accelerated molecular dynamics simulation method on a quantum-classical hybrid computing system

Patent metadata

Field	Value
Publication number	US-12424302-B2
Application number	US-202117162566-A
Country	US
Kind code	B2
Filing date	Jan 29, 2021
Priority date	Jan 29, 2020
Publication date	Sep 23, 2025
Grant date	Sep 23, 2025

Abstract

A method of performing computation using a hybrid quantum-classical computing system comprising a classical computer and a quantum processor includes computing, by use of a classical computer, short-range inter-particle interaction energies and self-energies of a group of interacting particles, transforming the quantum processor from an initial state to a charge-position encoded state, applying Quantum Fourier transformation to the quantum processor, measuring an estimated amplitude of the Fourier transformed superposition state on the quantum processor, computing long-range inter-particle interaction energies based on the measured estimated amplitude of the Fourier transformed superposition state, and computing and outputting a sum of the short-range inter-particle interaction energies, the self-energies of the system, and the long-range inter-particle interaction energies as a total inter-particle interaction energies of the system.

First claim

The invention claimed is:

1. A method of performing computation using a hybrid quantum-classical computing system comprising a classical computer and a quantum processor, comprising:
computing, by use of the classical computer and the quantum processor comprising a first register of a plurality of qubits, a second register of a plurality of qubits, and a third register of a plurality of qubits, multiple energies of a group of interacting particles of a molecular dynamics system that each have a particle index based on an Ewald summation method, the multiple energies comprising short-range inter-particle interaction energies, self-energies, and long-range inter-particle interaction energies, the computing of the multiple energies including:
computing long-range inter-particle interaction energies based on Fourier transformations to the quantum processor, the computing of the long-range inter-particle interaction energies including:
applying a first operation to the first register encoding the particle indices to transform the quantum processor from an initial state to an initial superposition state of the particle indices;
applying a second operation to the second register encoding positions of the interacting particles, and a third operation to the third register encoding charges of the interacting particles to transform the quantum processor from the initial superposition state of the particle indices to an intermediate superposition state;
applying a combination of single-qubit operations to the third register to transform the quantum processor from the intermediate superposition state to a phased intermediate superposition state, wherein the charges of the interacting particles are encoded in phases of the phased intermediate superposition state and the third register; and
applying an inverse operation of the third operation to the third register to transform the quantum processor from the phased intermediate superposition state to a charge-position encoded state; and

outputting, by use of the classical computer, the computed sum of the short-range inter-particle interaction energies, the self-energies of the system, and the long-range inter-particle interaction energies as a total inter-particle interaction energies of the molecular dynamics system.

2. The method according to claim 1 , wherein:
the computing of the multiple energies further includes computing the short-range inter-particle interaction energies and the self-energies,
the computing of the long-range inter-particle interaction energies further includes:
transforming the quantum processor from the charge-position encoded state to a Fourier transformed superposition state; and
measuring an estimated amplitude of the Fourier transformed superposition state on the quantum processor,

the computing of the multiple energies further includes:
computing long-range inter-particle interaction energies based on the measured estimated amplitude of the Fourier transformed superposition state; and
computing, by use of the classical computer, a sum of the short-range inter-particle interaction energies, the self-energies of the system, and the long-range inter-particle interaction energies.

3. The method according to claim 2 , wherein
the quantum processor comprises a group of trapped ions, each of which has two frequency-separated states defining a qubit, and
computing of the long-range inter-particle interaction energies further includes preparing the quantum processor in the initial state by setting, by a system controller, each trapped ion in the quantum processor in a superposition of the two frequency-separated states.

4. The method according to claim 1 , wherein transforming the quantum processor from the initial state to the charge-position encoded state comprises applying, by use of a system controller, a combination of gate operations to the quantum processor.

5. The method according to claim 4 , wherein the combination of gate operations comprises single-qubit gate operations and two-qubit gate operations.

6. The method according to claim 2 , wherein transforming the quantum processor from the charge-position encoded state to the Fourier transformed superposition state comprises applying, by use of a system controller, a combination of single-qubit operations and two-qubit operations to the quantum processor.

7. A hybrid quantum-classical computing system, comprising:
a quantum processor comprising a first register of a plurality of a plurality of qubits, a second register of a plurality of qubits, and a third register of a plurality of qubits, each qubit defined by two hyperfine states of a trapped ion;
one or more lasers configured to emit a laser beam, which is provided to trapped ions in the quantum processor;
a classical computer configured to:
compute multiple energies of a group of interacting particles of a molecular dynamics system that each have a particle index based on an Ewald summation method, the multiple energies comprising short-range inter-particle interaction energies, self-energies, and long-range inter-particle interaction energies, the computing of the multiple energies including:

computing long-range inter-particle interaction energies based on Fourier transformations to the quantum processor, the computing of the long-range inter-particle interaction energies including:
applying a first operation to the first register encoding the particle indices to transform the quantum processor from an initial state to an initial superposition state of the particle indices;
applying a second operation to the second register encoding positions of the interacting particles, and a third operation to the third register encoding charges of the interacting particles to transform the quantum processor from the initial superposition state of the particle indices to an intermediate superposition state;
applying a combination of single-qubit operations to the third register to transform the quantum processor from the intermediate superposition state to a phased intermediate superposition state, wherein the charges of the interacting particles are encoded in phases of the phased intermediate superposition state and the third register; and
applying an inverse operation of the third operation to the third register to transform the quantum processor from the phased intermediate superposition state to a charge-position encoded state; and

output the computed sum of the short-range inter-particle interaction energies, the self-energies of the system, and the long-range inter-particle interaction energies as a total inter-particle interaction energies of the molecular dynamics system; and
a system controller configured to control the emission of the laser beam from the one or more lasers.

8. The hybrid quantum-classical computing system according to claim 7 , wherein
the computing of the multiple energies further includes:
computing the short-range inter-particle interaction energies and the self-energies,

the system controller is further configured to:
transform the quantum processor from the charge-position encoded state to a Fourier transformed superposition state; and
measure an estimated amplitude of the Fourier transformed superposition state on the quantum processor, and

the computing of the multiple energies further includes:
computing long-range inter-particle interaction energies based on the measured estimated amplitude of the Fourier transformed superposition state; and
computing a sum of the short-range inter-particle interaction energies, the self-energies of the group of the interacting particles, and the long-range inter-particle interaction energies.

9. The hybrid quantum-classical computing system according to clai

Assignees

• Ionq Inc

Inventors

• Niroula Pradeep
• Zhang Wengang
• Nam Yunseong

Classifications

• G06N10/60

  Quantum algorithms, e.g. based on quantum optimisation, quantum Fourier or Hadamard transforms · CPC title

• G06F17/14

  Fourier, Walsh or analogous domain transformations {, e.g. Laplace, Hilbert, Karhunen-Loeve, transforms (for correlation function computation G06F17/156; spectrum analysers G01R23/16)} · CPC title

• G06F30/20

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title

• G06F2111/10

  Numerical modelling · CPC title

• G06N10/40

  Physical realisations or architectures of quantum processors or components for manipulating qubits, e.g. qubit coupling or qubit control · CPC title