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Characterizing transport in a quantum gas by measuring Drude weights
Philipp Schüttelkopf1, Mohammadamin Tajik1,2,3, Nataliia Bazhan1
1Vienna Center for Quantum Science and Technology (VCQ), Atominstitut, TU Wien, Vienna, Austria.
Science (New York, N.Y.)
|November 27, 2025
Summary
Researchers measured Drude weights in ultracold atomic gases, demonstrating dissipationless transport of charge carriers. This finding reveals ballistic propagation in strongly correlated quantum matter, even with interactions and at finite temperatures.
Area of Science:
- Condensed Matter Physics
- Quantum Gases
- Atomic Physics
Background:
- Transport properties determine material states like insulators, metals, and superconductors.
- The Drude weight is a key parameter quantifying ballistic charge carrier transport.
Purpose of the Study:
- To measure Drude weights in one-dimensional ultracold interacting bosonic gases.
- To characterize atomic and energy currents under applied force and system joining.
Main Methods:
- Utilized ultracold atomic gases confined to one dimension.
- Applied a constant force to induce currents.
- Joined two subsystems prepared in different equilibrium states.
Main Results:
- Successfully measured Drude weights in the ultracold atomic gas system.
- Demonstrated dissipationless transport, indicating ballistic propagation.
- Observed this phenomenon even with interactions and at finite temperatures.
Conclusions:
- The study provides a robust framework for characterizing transport in strongly correlated quantum matter.
- The findings are applicable to regimes where theoretical models are incomplete.
- Ballistic propagation of conserved quantities was confirmed, aligning with lowest order hydrodynamics.
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