Geometrical characterization of reduced density matrices reveals quantum phase transitions in many-body systems

摘要

<正>Quantum phase transitions (QPTs) play a central role for understanding many-body physics (1)Different from classical phase transitions which are driven by thermal fluctuations, QPTs are driven by quantum fluctuations at zero temperature and can be accessed by varying some physical parameters of the many-body system. Characterizing QPTs, which normally needs complicated theoretical calculations, becomes a fundamental problem to further study quantum matters. Here a group of physicists proposed to connect the geometrical properties of reduced density matrices (RDMs) of the physical system with its quantum phase transitions [2,3]