Disorder-Induced Dephasing in Backscattering-Free Quantum Transport

Area of Science:

• Quantum physics
• Condensed matter physics
• Quantum information science

Background:

• Disorder can disrupt quantum state transport, a critical phenomenon in systems like topological insulators and photonic media.
• Understanding quantum state propagation under disorder is essential for quantum information processing and material science.

Purpose of the Study:

• To analyze disorder-perturbed quantum state transport in the absence of backscattering.
• To quantify disorder-induced dephasing and identify conditions for maintaining backscattering-free transport.
• To examine the full disorder-averaged quantum state, including populations and coherences.

Main Methods:

• Analysis of quantum state transport in disordered systems.
• Quantification of disorder-induced dephasing.
• Identification of a gap condition for backscattering-free transport.
• Treatment of nonequilibrium dynamics using Lindblad master equations.

Main Results:

• Disorder-induced dephasing is shown to be bound.
• A specific gap condition is identified that preserves the backscattering-free regime despite momentum broadening.
• The analysis covers both populations and coherences of the quantum state.

Conclusions:

• The study provides a comprehensive analysis of quantum state transport under disorder.
• The findings offer insights into preserving quantum information in realistic, disordered systems.
• The developed framework is applicable to various physical systems exhibiting backscattering-free transport.