à 
(QC) Canada

Amplitude mode contribution to the Meissner effect in Fulde Ferrell superfluids
Rufus Boyack
Université de Montréal.

Présentation en anglais.

Lien Zoom: https://umontreal.zoom.us/j/93026432919
Meeting ID: 930 2643 2919
Passcode: écrire en chiffre: un, trois, sept.

Abstract: One of the fundamental properties of superconductors is the Meissner effect, whereby an external magnetic field is expelled from the superconductor. In uniform superfluids, which have a rotation and translation invariant pairing gap, the response of the gap to the external field does not contribute to the Meissner effect. Indeed, it is traditionally thought that the mode characterising the response of the amplitude of the gap is difficult to observe in conventional superconductors. In this talk I will present an overview of the Meissner effect and then focus on a gauge-invariant calculation of the superfluid density in what is known as the Fulde-Ferrell (FF) superfluid, which has Cooper pairs with finite center of mass momentum. For the FF superfluid, the amplitude-mode response of the gap provides a large contribution to the Meissner response. In charged superfluids this amplitude mode is the condensed-matter analogue of the Higgs mode, and thus the Meissner response in these non-uniform superconductors provides a convenient way to observe their effects. 

For more information about Rufus, you can consult his Google Scholar web page.

Cette conférence est présentée par le RQMP.