Quantum simulation of dynamical phase transitions

Time evolution of the magnetization and time-averaged magnetization as a function of transverse field. Credit: IOP

Researchers from the Institute of Physics of the Chinese Academy of Sciences, Zhejiang University and RIKEN in Japan, has successfully performed quantum simulation of Dynamical Phase Transitions (DPT) in a Lipkin-Meshkov-Glick model with a 16-qubit superconducting quantum simulator.

Dynamical phase transition is a kind of nonequilibrium phase transition and has been theoretically investigated in various quantum many-body models. There are two types of DPT. The first type (DPT-1) focuses on the non-equilibrium order parameter, while the second type (DPT-2) is characterized by the non-analytical behaviors of Loschmidt echo associated with the Lee-Yang-Fisher zeros in statistical mechanics.

The quantum processor integrates 20 superconducting qubits, all coupled to a common resonator bus, which was used to generate Schrödinger cat states in previous work. This time, 16 qubits were used to engineer the Lipkin-Meshkov-Glick (LMG) model by applying controllable transverse field to each qubit. The system is driven into a non-equilibrium state with microwaves and then evolved under the LMG model.

This study has been published in Science Advances.

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