Absorption to Fluctuating Bunching States in Non-Unitary Boson Dynamics

TL;DR

This paper demonstrates that noisy nonunitary boson dynamics lead to a unique fluctuating bunching state, characterized by rapid absorption and universal relaxation behavior, distinct from unitary or noiseless nonunitary systems.

Contribution

It introduces the concept of the noisy spectral gap and reveals the universal power-law relaxation in noisy nonunitary boson dynamics.

Findings

Noisy nonunitary dynamics induce a unique fluctuating bunching state.

Absorption to the state occurs exponentially fast asymptotically.

Relaxation times follow a universal power law with respect to noise.

Abstract

We show that noisy nonunitary dynamics of bosons drives arbitrary initial states into a novel fluctuating bunching state, where all bosons occupy one time-dependent mode. We propose a concept of the noisy spectral gap, a generalization of the spectral gap in noiseless systems, and demonstrate that the exponentially fast absorption to the fluctuating bunching state takes place asymptotically. The fluctuating bunching state is unique to noisy nonunitary dynamics, with no counterpart in any unitary dynamics and nonunitary dynamics described by a time-independent generator. We also argue that the times of relaxation to the fluctuating bunching state obey a universal power law as functions of the noise parameter in generic noisy nonunitary dynamics.