Information constraint in open quantum systems

TL;DR

This paper introduces the concept of information constraint in open quantum systems, characterizes it analytically, and explains phenomena like chiral damping and edge modes through this new framework.

Contribution

It defines the information constraint, derives its analytical form for quadratic Lindbladian systems, and links it to damping phenomena and edge mode correspondence in open quantum systems.

Findings

Analytical representation of information constraint ($I_C$) for quadratic Lindbladian systems.

Explanation of chiral and helical damping via information constraint.

Identification of Dirac damping as a new damping mode.

Abstract

We propose an effect called information constraint which is characterized by the existence of different decay rates of signal strengths propagating along opposite directions. It is an intrinsic property of a type of open quantum system, which does not rely on boundary conditions. We define the value of information constraint ($I_C$) as the ratio of different decay rates and derive the analytical representation of $I_C$ for general quadratic Lindbladian systems. Based on information constraint, we can provide a simple and elegant explanation of chiral and helical damping, and get the local maximum points of relative particle number for the periodical boundary system, consistent with numerical calculations. Inspired by information constraint, we propose and prove the correspondence between edge modes and damping modes. A new damping mode called Dirac damping is constructed, and chiral/helical damping can be regarded as a special case of Dirac damping.