We study the response to an applied flux of an interacting system of Dirac-Weyl fermions confined in a one-dimensional (1D) ring. Combining analytical calculations with density-matrix renormalization group results, we show that tuning of the interactions leads to a unique many-body system that displays either a suppression or an enhancement of the Drude weight - the zero-frequency peak in the ac conductivity - with respect to the noninteracting value. An asymmetry in the interaction strength between same- and different-pseudospin Dirac-Weyl fermions leads to Drude weight enhancement. Vice versa, symmetric interactions lead to Drude weight suppression. Our predictions can be tested in mixtures of ultracold fermions in 1D ring traps.
Tuning the Drude weight of Dirac-Weyl fermions in one-dimensional ring traps
Polini M.;
2017-01-01
Abstract
We study the response to an applied flux of an interacting system of Dirac-Weyl fermions confined in a one-dimensional (1D) ring. Combining analytical calculations with density-matrix renormalization group results, we show that tuning of the interactions leads to a unique many-body system that displays either a suppression or an enhancement of the Drude weight - the zero-frequency peak in the ac conductivity - with respect to the noninteracting value. An asymmetry in the interaction strength between same- and different-pseudospin Dirac-Weyl fermions leads to Drude weight enhancement. Vice versa, symmetric interactions lead to Drude weight suppression. Our predictions can be tested in mixtures of ultracold fermions in 1D ring traps.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.