Disorder-Assisted Adiabaticity in Correlated Many-Particle Systems

TL;DR

This paper shows that adding disorder to a quantum system can help it respond more adiabatically during interaction pulses, reducing energy changes and improving control.

Contribution

The study reveals that disorder enhances adiabaticity in quantum systems, regardless of pulse shape or strength, and identifies triangular pulses as the most effective.

Findings

Longer pulse durations reduce the change in total energy in the system.

Increasing disorder strength suppresses residual energy after interaction pulses.

Triangular pulses produce the smallest energy change compared to other pulse shapes.

Abstract

We investigate how disorder affects adiabaticity in an interacting quantum system by assessing its effect on the state of the system after an interaction modulation, or interaction “pulse”, whereby the interaction is changed from zero to a maximum value and then back to zero following a given time profile. We find that, independently of the disorder strength and pulse shapes (rectangular, triangular, and Gaussian), the pulse duration is negatively correlated with the change in total energy in the system. That is, a longer duration reduces the change in total energy for each protocol. Most importantly, across different considered pulse shapes, we find a robust negative correlation between the disorder strength and the change in total energy across the interaction pulse. Namely, increasing the disorder strength systematically suppresses the residual energy added to the system after the interaction pulse, indicating a more adiabatic response. These two effects, disorder-induced and duration-induced adiabaticity, are consistently observed across all three pulse shapes. Among the protocols, the triangular pulse yields the smallest change in total energy in the system over comparable conditions, demonstrating the most adiabatic response. In addition to the energy analysis, we also examine how disorder modifies the effective temperature change across the interaction pulse, to further establish a quantitative relation between disorder and the thermal response. Altogether, our results identify disorder as a key factor in both the energy and the temperature variation over the time-modulation of the interaction.

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