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Related Experiment Video

Updated: Jul 3, 2026

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform

Published on: August 2, 2019

Work fluctuations in quantum spin chains.

Sven Dorosz¹, Thierry Platini, Dragi Karevski

¹Department of Physics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061-0435, USA.

Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics

|July 23, 2008

Summary

This study explores work fluctuations in quantum spin chains under magnetic fields, verifying fluctuation relations. It reveals maximum work fluctuations at specific frequencies in the Ising model and transitions in work distribution for the XX model.

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Last Updated: Jul 3, 2026

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform

Published on: August 2, 2019

Area of Science:

Quantum mechanics
Statistical mechanics
Condensed matter physics

Background:

The fluctuation relation and Jarzynski equality are key concepts in non-equilibrium statistical mechanics.
Quantum spin chains are fundamental models for studying complex quantum phenomena.
Understanding work fluctuations in quantum systems is crucial for developing quantum technologies.

Purpose of the Study:

To investigate work fluctuations in integrable (Ising) and nonintegrable (XX) quantum spin chains.
To numerically test the quantum Crooks and Jarzynski relations under various magnetic field protocols.
To analyze the behavior of work fluctuations in a forcing regime with periodic magnetic fields.

Main Methods:

Numerical simulations of quantum spin chains (Ising and XX models).
Application of time-dependent longitudinal magnetic fields with different protocols.
Exact analytical solutions for the Ising model using double-confluent Heun functions.
Analysis of work distribution functions under varying field frequencies.

Main Results:

The quantum Crooks and Jarzynski relations are numerically verified for both chain types.
An exact solution for the Ising model in a periodic magnetic field is derived.
Work fluctuations in the Ising model exhibit maxima at frequencies proportional to field amplitude.
The nonintegrable XX model shows a transition from Poisson to normal work distributions based on field frequency.

Conclusions:

The fluctuation relations hold for the studied quantum spin chain models.
Periodic driving reveals distinct behaviors in work fluctuations for integrable and nonintegrable systems.
The findings provide insights into quantum thermodynamics and the dynamics of driven quantum systems.