Dissipative quantum gas of light
The understanding of quantum systems in our textbooks often comes from modeling these systems isolated from the environment. However, an emerging focus is to understand how many-body quantum systems behave when interacting with their surroundings, and how they subsequently become dissipative or non-Hermitian systems. Öztürk Wait. By trapping photons in the optical cavity to form light quantum condensation, the optical cavity is a naturally dissipative system. By changing the capture conditions, they proved that the system provides a powerful platform for exploring the complex dynamics and phase transitions that occur in dissipative quantum systems.
science, This question p. 88
The quantum gas of light (such as photons or polaron condensate in an optical microcavity) is a collective quantum system that can adjust the dissipation of, for example, cavity losses. This feature makes them a tool for studying the dissipative phase, which is an emerging subject in quantum many-body physics. We experimentally proved that the non-hermitian phase of the photon Bose-Einstein condensate changes to a dissipative phase characterized by the double exponential decay of the second-order coherence of the condensate. Due to the occurrence of abnormal points in the quantum gas, a phase change has occurred. Although Bose-Einstein condensation is usually related to lasing through smooth junctions, the observed phase transition distinguishes the bi-exponential phase from lasing and the intermediate oscillating condensation. Our method can be used to study various dissipative quantum phases in topological or lattice systems.