Embedding the Yang-Lee quantum criticality in open quantum systems
Norifumi Matsumoto, Masaya Nakagawa, Masahito Ueda
Abstract
The Yang-Lee edge singularity is a quintessential nonunitary critical phenomenon characterized by anomalous scaling. However, an imaginary magnetic field involved in this phenomenon makes its physical implementation nontrivial. By embedding the original classical system which exhibits the Yang-Lee edge singularity in a quantum system with an ancilla qubit and by invoking the quantum-classical correspondence, we demonstrate a physical realization of the nonunitary quantum criticality in an open quantum system, where the nonunitary criticality is identified with the singularity at an exceptional point caused by postselection of quantum measurement.
Topics & Concepts
SingularityQuantumPhysicsQubitCriticalityOpen quantum systemQuantum mechanicsQuantum processQuantum discordQuantum operationTheoretical physicsQuantum dynamicsMathematicsGeometryNuclear physicsQuantum Mechanics and Non-Hermitian PhysicsQuantum many-body systemsQuantum chaos and dynamical systems