Browsing by Author "Guenther, Nils Eric"
Now showing items 1-5 of 5
-
Bose polarons at finite temperature and strong coupling
Guenther, Nils Eric; Massignan, Pietro Alberto; Lewenstein, Maciej; Bruun, Georg (2018-02-01)
Article
Open AccessA mobile impurity coupled to a weakly interacting Bose gas, a Bose polaron, displays several interesting effects. While a single attractive quasiparticle is known to exist at zero temperature, we show here that the spectrum ... -
Dynamics of quantum mixtures
Guenther, Nils Eric (Universitat Politècnica de Catalunya, 2021-09-08)
Doctoral thesis
Open AccessAt sufficiently low temperatures, fluids of bosonic particles may undergo a phase transition, below which a Bose-Einstein condensate (BEC) forms. The BEC is one of the most fundamental concepts in many-body quantum physics ... -
Mobile impurity in a Bose-Einstein condensate and the orthogonality catastrophe
Guenther, Nils Eric; Schmidt, Richard; Bruun, Georg M.; Gurarie, Victor; Massignan, Pietro Alberto (American Physical Society, 2021-01-01)
Article
Open AccessWe analyze the properties of an impurity in a dilute Bose-Einstein condensate (BEC). First the quasiparticle residue of a static impurity in an ideal BEC is shown to vanish with increasing particle number as a stretched ... -
Quantized superfluid vortex dynamics on cylindrical surfaces and planar annuli
Guenther, Nils Eric; Massignan, Pietro Alberto; Fetter, Alexander L. (AMER PHYSICAL SOC, 2017-12-06)
Article
Open AccessSuperfluid vortex dynamics on an infinite cylinder differs significantly from that on a plane. The requirement that a condensate wave function be single valued upon once encircling the cylinder means that such a single ... -
Superfluid vortex dynamics on a torus and other toroidal surfaces of revolution
Guenther, Nils Eric; Massignan, Pietro Alberto; Fetter, Alexander L. (American Physical Society (APS), 2020-05-04)
Article
Open AccessThe superfluid flow velocity is proportional to the gradient of the phase of the superfluid order parameter, leading to the quantization of circulation around a vortex core. In this work, we study the dynamics of a ...