arXiv subjects

A. Korolyuk

Publications and source records attributed to A. Korolyuk.

3 recordsLinked to original sources

arXiv2013

Collective excitations of a trapped Fermi gas at finite temperature

We study collective excitations of a trapped Fermi gas at finite temperature using the Bogoliubov-deGennes mean-field theory in conjunction with the generalized random phase approximation. The collective excitations are analyzed through the density response of a monopole excitation. We show the appearance of several modes at the normal fluid - superfluid phase transition temperature: Higgs mode-like pairing amplitude modulations, analogues of the second sound in the trapped gas, and an edge mode that is also the strongest mode in the response.

cond-mat.quant-gas↗

arXiv2011

Density response of a trapped Fermi gas: a crossover from the pair vibration mode to the Goldstone mode

We consider the density response of a trapped two-component Fermi gas. Combining the Bogoliubov-deGennes method with the random phase approximation allows the study of both collective and single particle excitations. Calculating the density response across a wide range of interactions, we observe a crossover from a weakly interacting pair vibration mode to a strongly interacting Goldstone mode. The crossover is associated with a depressed collective mode frequency and an increased damping rate, in agreement with density response experiments performed in strongly interacting atomic gases.

cond-mat.quant-gas↗

arXiv2010

Probing the FFLO phase by double occupancy modulation spectroscopy

We propose here that for a spin-imbalanced two-component attractive Fermi gas loaded in a 1D optical lattice in presence of an harmonic confining potential, the observation of the change in the double occupancy after a lattice depth modulation can provide clear evidence of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase. Simulating the time evolution of the system, we can characterize the double occupancy spectrum for different initial conditions, relating its features to the FFLO wavevector $q$. In particular, the narrowing of the width of the spectrum can be related, through Bethe-ansatz equations in the strongly interacting limit, to the FFLO wavevector $q$.

cond-mat.quant-gas↗