Emergence of steady quantum transport in a superconducting processor

Area of Science:

• Quantum physics
• Condensed matter physics
• Quantum information science

Background:

• Non-equilibrium quantum transport is vital for technologies like nanoelectronics and thermal management.
• Understanding requires simulating both macroscopic and microscopic quantum phenomena.
• Quantum transport involves coherent energy and particle transfer through quantum channels between thermodynamic baths.

Purpose of the Study:

• To experimentally demonstrate non-equilibrium steady quantum transport.
• To investigate the emergence of steady particle currents between emulated thermodynamic baths.
• To explore the tunability of these currents via macroscopic bath properties.

Main Methods:

• Utilized a superconducting quantum processor to emulate thermodynamic baths with qubit ladders.
• Realized and measured steady particle currents between the emulated baths.
• Employed single-site resolution for precise control and measurement of quantum systems.

Main Results:

• Successfully demonstrated the emergence of non-equilibrium steady quantum transport.
• Observed particle currents independent of bath initialization details.
• Showcased temporal fluctuation decrease with bath size, aligning with thermodynamic predictions.
• Provided experimental evidence for pure-state statistical mechanics and prethermalization.
• Tuned steady currents by manipulating macroscopic bath properties like filling and spectral characteristics.

Conclusions:

• The study establishes a novel experimental platform for exploring non-equilibrium quantum transport.
• Findings offer insights into fundamental aspects of quantum statistical mechanics in driven systems.
• Paves the way for future research in strongly correlated quantum matter and quantum technologies.