Arithmetic apparatus, method, and program
View Patent ↗An arithmetic apparatus includes an arithmetic unit configured to adjust an intensity schedule function in quantum annealing of a constraint term expressed by many-body interactions in an LHZ model by a hybrid algorithm that uses a value of the intensity schedule function at one time point or each of a plurality of time points as a variational parameter.
1 . An arithmetic apparatus comprising:
a quantum computing machine comprising a semiconductor control device and a quantum annealing circuit having an LHZ (Lechner-Hauke-Zoller) model implemented using hardware;
at least one memory storing instructions; and
at least one processor configured to execute the instructions to:
control the semiconductor control device to receive an intensity schedule function; and
control the semiconductor control device to adjust the intensity schedule function in quantum annealing of a constraint term expressed by many-body interactions in the LHZ model by a hybrid algorithm that uses a value of the intensity schedule function at one time point or each of a plurality of time points as a variational parameter, wherein the intensity schedule function is adjusted by the hybrid algorithm, the hybrid algorithm executing fitting processing of fitting the value of the variational parameter at the one time point or each of the plurality of time points by a smooth function and update processing of updating the variational parameter in such a way that an energy expectation value decreases based on a result of executing the quantum annealing on the LHZ model using the smooth function as the intensity schedule function.
2 . The arithmetic apparatus according to claim 1 , wherein the smooth function is a polynomial function.
3 . The arithmetic apparatus according to claim 1 , wherein the quantum annealing circuit is configured to change an intensity of interactions between a plurality of quantum bits that form the LHZ model based on a result of the fitting processing.
4 . The arithmetic apparatus according to claim 1 , wherein
the processor is further configured to execute the instructions to:
acquire, after adjusting the intensity schedule function by the hybrid algorithm, the result of executing the quantum annealing based on the adjusted intensity schedule function.
5 . The arithmetic apparatus according to claim 1 , wherein the quantum annealing circuit comprises a plurality of quantum bit circuits coupled to one another.
6 . The arithmetic apparatus according to claim 5 , wherein the quantum computing machine further comprises a semiconductor reading device configured to read states of the plurality of quantum bit circuits.
7 . An arithmetic method comprising:
controlling a semiconductor control device of a quantum computing machine to receive an intensity schedule function;
controlling a quantum annealing circuit of the quantum computing machine which has an LHZ (Lechner-Hauke-Zoller) model implemented using hardware;
adjusting, using the semiconductor control device, the intensity schedule function in quantum annealing of a constraint term expressed by many-body interactions in the LHZ model by a hybrid algorithm that uses a value of the intensity schedule function at one time point or each of a plurality of time points as a variational parameter; and
adjusting, using the semiconductor control device, the intensity schedule function by the hybrid algorithm, the hybrid algorithm executing fitting processing of fitting the value of the variational parameter at the one time point or each of the plurality of time points by a smooth function and update processing of updating the variational parameter in such a way that an energy expectation value decreases based on a result of executing the quantum annealing on the LHZ model using the smooth function as the intensity schedule function.
8 . The arithmetic method according to claim 7 , wherein the smooth function is a polynomial function.
9 . The arithmetic method according to claim 7 , comprising changing an intensity of interactions between a plurality of quantum bits that form the LHZ model based on a result of the fitting processing.
10 . A non-transitory computer readable medium storing a program causing a computer to execute processing of:
controlling a semiconductor control device of a quantum computing machine to receive an intensity schedule function;
controlling a quantum annealing circuit of the quantum computing machine which has an LHZ (Lechner-Hauke-Zoller) model implemented using hardware;
adjusting, using the semiconductor control device, the intensity schedule function in quantum annealing of a constraint term expressed by many-body interactions in the LHZ model by a hybrid algorithm that uses a value of the intensity schedule function at one time point or each of a plurality of time points as a variational parameter; and
adjusting, using the semiconductor control device, the intensity schedule function by the hybrid algorithm, the hybrid algorithm executing fitting processing of fitting the value of the variational parameter at the one time point or each of the plurality of time points by a smooth function and update processing of updating the variational parameter in such a way that an energy expectation value decreases based on a result of executing the quantum annealing on the LHZ model using the smooth function as the intensity schedule function.