Condensed Matter Seminar: Thermodynamics of a one-dimensional Bose gas with repulsive contact interactions

Giulia De Rosi (Universitat Politècnica de Catalunya)
I present a thorough study of the thermodynamics of a one-dimensional repulsive Bose gas, focusing in particular on corrections beyond the Luttinger-liquid description.

Giulia De Rosi (Universitat Politècnica de Catalunya)
Online Seminar
Mon 29. January 2020, 11:30 am (MEZ)

Abstract:

I present a thorough study of the thermodynamics of a one-dimensional repulsive Bose gas, focusing in particular on corrections beyond the Luttinger-liquid description.
We computed the chemical potential, pressure, and Tan’s contact as a function of temperature and gas parameter with an exact thermal Bethe ansatz. In addition, we provided interpretations of the main features in the analytically tractable regimes, based on a variety of approaches (Bogoliubov, hard core, Sommerfeld, and virial). The beyond-Luttinger-liquid thermodynamic effects are found to be nonmonotonic as a function of gas parameter. Such behavior is explained in terms of nonlinear dispersion and “negative excluded volume” effects, for weak and strong repulsion, respectively, responsible for the opposite sign corrections in the thermal next-to-leading term of the thermodynamic quantities at low temperatures. Our predictions can be applied to other systems including super Tonks-Girardeau gases, dipolar and Rydberg atoms, helium, quantum liquid droplets in bosonic mixtures, and impurities in a quantum bath.

References

[1] Giulia De Rosi, Pietro Massignan, Maciej Lewenstein, and Grigori E. Astrakharchik, “Beyond-Luttinger-liquid thermodynamics of a one-dimensional Bose gas with repulsive contact interactions”, Phys. Rev. Research 1, 033083 (2019).
[2] Giulia De Rosi, Grigori E. Astrakharchik, and Sandro Stringari, “Thermodynamic behavior of a one-dimensional Bose gas at low temperature”, Phys. Rev. A 96, 013613 (2017).