4 papers · 1 filter
Probing XY phase transitions in a Josephson junction array with tunable frustration
R. Cosmic, K. Kawabata, Y. Ashida +5
The seminal theoretical works of Berezinskii, Kosterlitz, and Thouless presented a new paradigm for phase transitions in condensed matter that are driven by topological excitations…
Deep Reinforcement Learning Control of Quantum Cartpoles
Zhikang T. Wang, Yuto Ashida, Masahito Ueda
We generalize a standard benchmark of reinforcement learning, the classical cartpole balancing problem, to the quantum regime by stabilizing a particle in an unstable potential thr…
Topological unification of time-reversal and particle-hole symmetries in non-Hermitian physics
Kohei Kawabata, Sho Higashikawa, Zongping Gong +2
Topological phases are enriched in non-equilibrium open systems effectively described by non-Hermitian Hamiltonians. While several properties unique to non-Hermitian topological sy…
Information Retrieval and Criticality in Parity-Time-Symmetric Systems
Kohei Kawabata, Yuto Ashida, Masahito Ueda
By investigating information flow between a general parity-time (PT) -symmetric non-Hermitian system and an environment, we find that the complete information retrieval from the en…