Temperature-Dependent Periodicity of the Persistent Current in Strongly Interacting Systems

Area of Science:

• Condensed Matter Physics
• Ultracold Atomic Gases
• Quantum Many-Body Physics

Background:

• Persistent currents are equilibrium currents in isolated systems, previously studied in metals.
• Recent experiments generate atomic persistent currents in ultracold gases, necessitating new theoretical approaches.
• Understanding persistent currents in interacting systems at finite temperatures remains a challenge.

Purpose of the Study:

• Investigate persistent currents in the fermionic one-dimensional Hubbard model at strong interaction limits.
• Explore the influence of temperature on persistent current properties.
• Identify phenomena missed by single-particle and Luttinger liquid theories.

Main Methods:

• Theoretical analysis of the fermionic one-dimensional Hubbard model.
• Focus on the strongly interacting regime.
• Examination of temperature and polarization effects on persistent currents.

Main Results:

• Observed temperature-driven changes in the flux period and sign (diamagnetic/paramagnetic) of persistent currents.
• Demonstrated counterintuitive increase in current magnitude with temperature.
• Identified varying decay rates of current based on system polarization.

Conclusions:

• Strongly interacting multicomponent systems exhibit unique persistent current properties not captured by conventional methods.
• Findings are crucial for interpreting experiments on persistent currents in ultracold atomic gases.
• Highlights the limitations of single-particle and Luttinger liquid approximations for these systems.