Observation of disorder-free localization using a (2+1)D lattice gauge theory on a quantum processor

Area of Science:

• Quantum physics
• Condensed matter theory
• Computational physics

Background:

• Disorder-induced phenomena in quantum many-body systems are computationally challenging.
• Existing analytical and numerical methods struggle with relevant time and system scales for disorder sampling.

Purpose of the Study:

• To investigate quantum circuits initialized in tunable superpositions over all disorder configurations.
• To reduce the computational cost of disorder sampling in quantum many-body systems.
• To explore the nature of localization in the absence of disorder.

Main Methods:

• Initialization of quantum circuits in superposition states across disorder configurations.
• Observation of system evolution on experimentally accessible timescales.
• Entropy measurements to compare superposition-prepared states with direct disorder sampling.

Main Results:

• Observed localization in one and two dimensions without any disorder.
• Perturbations failed to diffuse in disorder-free evolution and initial states.
• Entropy measurements confirmed fundamental differences between superposition-prepared and directly sampled states.

Conclusions:

• Superposition states offer a distinct pathway for studying quantum many-body systems.
• The proposed algorithm provides a polynomial speedup for sampling disorder configurations.
• This work addresses a long-standing challenge in many-body localization studies.