Localization-delocalization effects of a delocalizing dissipation on disordered XXZ spin chains

Area of Science:

• Quantum mechanics
• Condensed matter physics
• Statistical mechanics

Background:

• The interplay of interaction, disorder, and dissipation leads to complex phenomena in quantum systems.
• A disordered XXZ spin chain is studied in contact with a bath driving it towards a delocalized Dicke state.

Purpose of the Study:

• Investigate localization phenomena in a disordered XXZ spin chain under dissipation.
• Analyze the conditions under which localized states emerge despite the presence of a bath.

Main Methods:

• Analysis of the single-particle density matrix and its natural orbitals.
• Calculation of averaged steady-state occupation in the eigenbasis of the open system Hamiltonian.
• Utilizing a concatenated inverse participation ratio to quantify localization.

Main Results:

• Localized natural orbitals are found in the steady state under strong disorder, irrespective of interaction strength.
• Steady-state occupation can exhibit exponential decay or be more evenly spread depending on disorder and interaction strength.
• Strong dissipation reduces localization signatures by increasing the coherence of steady states.

Conclusions:

• Localization can persist in disordered quantum systems even when coupled to a dissipative bath.
• The degree of localization is sensitive to the interplay between disorder, interaction, and dissipation strength.
• A combined inverse participation ratio effectively captures localization signatures in open quantum systems.