News
We posted a preprint that extensively analyzes penalty methods in variational quantum eigensolver to obtain a specific symmetric quantum state.
We posted a preprint that extensively analyzes penalty methods in variational quantum eigensolver to obtain a specific symmetric quantum state.
We propose a method for calculating the energy and band structure of solid-state systems using a quantum computer.
Dr. Nakagawa at QunaSys, Dr. Yoshioka at RIKEN (former QunaSys intern), Dr. Ohnishi at JSR Corp., and Dr. Mizukami at Osaka Univ (QunaSys advisor) posted a preprint on the use of variational quantum algorithms to calculate the band structure of solid-state systems.
We propose a method to utilize small-sized quantum computers to solve large systems.
Prof. Fujii (QunaSys Chief Advisor), Assistant Prof. Mitarai (QunaSys CSO), Special Associate Prof. Mizukami (QunaSys Advisor) from Osaka University, and Dr. Nakagawa from QunaSys have devised a method called "Deep VQE" that enables computation on large systems by iteratively using small-size quantum computers. The preprint is now available as "Deep Variational Quantum Eigensolver: a divide-and-conquer method for solving a larger problem with smaller size quantum computers".
We proposed a general methodology for evaluating the optimal resource cost required for error mitigation.
Ryuji Takagi (distinguished visiting researcher) from QunaSys Inc. proposed a general methodology for evaluating the optimal resource cost required for one of the most promising error mitigation methods for near-term devices, employing ideas and techniques developed in the field known as quantum resource theories.
We proposed VQE-based algorithms for calculating nonadiabatic couplings and Berry’s phase.
Tamiya (intern) and Nakagawa from QunaSys Inc. proposed new near-term quantum algorithms for calculating first- and second-order nonadiabatic couplings (NACs) and Berry’s phase, which are important quantities for analyzing properties of molecules and materials.
We proposed a near-term quantum machine learning algorithm for computing the excited state properties of a molecule.
Kawai (intern) and Nakagawa from QunaSys Inc. proposed a near-term quantum machine learning algorithm for computing the excited state properties of a molecule, which are crucial for studies in quantum chemistry.
We proposed a method for calculating transition amplitudes of molecules on a near-term quantum computer.
We released a paper (preprint) for calculating transition amplitudes of molecules, which are important quantities in photochemistry, authored by Ibe, Nakagawa, Yamamoto, and Mitarai from QunaSys Inc. and Dr. Gao and Dr. Kobayashi at Mitsubishi Chemical Corp. Science & Innovation Center.
Our algorithm improves the efficiency of chemistry calculations on a quantum computer
We released a new algorithm called orbital optimized unitary coupled cluster (OO-UCC) for improving the efficiency of chemistry calculations on a quantum computer with our advisor Assoc. Prof. Wataru Mizukami (Quantum information and biology division, Osaka Univ.) as the first author of the paper (preprint). Mitarai, Nakagawa, Yamamoto, and Yan at QunaSys Inc. and Dr. Ohnishi at JSR Corporation contributed to the work as co-authors.
We proposed near-term quantum algorithms for calculating the Green’s function.
Endo (intern), Kurata (intern), and Nakagawa from QunaSys Inc. proposed a near-term quantum algorithm for computing the Green’s function, which is crucial for analyzing properties of molecules and materials. Now you can read the preprint of the paper on arXiv.
We published an algorithm to calculate the non-equilibrium steady states using a quantum computer.
Yoshioka, Nakagawa, and Mitarai from QunaSys Inc., and our advisor, Prof. Fujii, published a paper (preprint) that proposed an algorithm named “dissipative-system Variational Quantum Eigensolver (dVQE)” to simulate the non-equilibrium steady state on a quantum computer.