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Updated: Oct 21, 2025
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Hydrodynamic nonlinear response of interacting integrable systems
Michele Fava1, Sounak Biswas2, Sarang Gopalakrishnan3
1Rudolf Peierls Centre for Theoretical Physics, Clarendon Laboratory, Oxford OX1 3PU, United Kingdom; michele.fava@physics.ox.ac.uk.
Summary
We developed a new method to calculate the nonlinear response of interacting integrable systems. This approach accurately describes systems in the hydrodynamic limit and distinguishes them from noninteracting ones.
Area of Science:
- Condensed matter physics
- Quantum many-body systems
- Statistical mechanics
Background:
- Understanding the nonlinear response of quantum systems is crucial for characterizing their dynamics.
- Integrable systems offer a unique platform to study many-body interactions due to their exact solvability.
- Distinguishing between interacting and noninteracting integrable systems is key to understanding emergent phenomena.
Purpose of the Study:
- To develop a general formalism for computing the nonlinear response of interacting integrable systems.
- To provide a method for calculating finite-temperature Drude weights.
- To identify and characterize nonperturbative regimes in nonlinear response.
Main Methods:
- Development of a theoretical formalism for nonlinear response calculations.
- Asymptotic analysis in the hydrodynamic limit.
- Application to specific models like the Lieb-Liniger gas and the XXZ spin chain.
- Comparison with numerical evaluations.
Main Results:
- A formalism for asymptotically exact nonlinear response in the hydrodynamic limit.
- Spatially resolved nonlinear response as a signature distinguishing interacting from noninteracting integrable systems.
- A prescription for computing finite-temperature Drude weights of arbitrary order.
- Identification of intrinsically nonperturbative regimes.
Conclusions:
- The developed formalism provides a powerful tool for studying nonlinear phenomena in integrable systems.
- The study highlights the importance of spatially resolved measurements for characterizing quantum systems.
- The findings offer new insights into the behavior of interacting quantum matter.
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