In this review, we discuss the properties of a few impurity atoms immersed in a gas of
ultracold fermions—the so-called Fermi polaron problem. On one hand, this many-body …

This article reviews theoretical and experimental developments for one-dimensional Fermi
gases. Specifically, the experimentally realized two-component delta-function interacting …

The dynamics of a mobile quantum impurity in a degenerate Fermi system is a fundamental
problem in many-body physics. The interest in this field has been renewed due to recent …

Interactions between quasiparticles are of fundamental importance and ultimately determine
the macroscopic properties of quantum matter. A famous example is the phenomenon of …

The problem of an impurity particle moving through a bosonic medium plays a fundamental
role in physics. However, the canonical scenario of a mobile impurity immersed in a Bose …

When an impurity is immersed in a Bose-Einstein condensate, impurity-boson interactions
are expected to dress the impurity into a quasiparticle, the Bose polaron. We superimpose …

Ultracold quantum gases offer a unique setting for quantum simulation of interacting many-
body systems. The high degree of controllability, the novel detection possibilities and the …

The notion of quasi-particles is essential for understanding the behaviour of complex many-
body systems. A prototypical example of a quasi-particle is a polaron, formed by an impurity …

The emergence of quasiparticles in interacting matter represents one of the cornerstones of
modern physics. However, in the vicinity of a quantum critical point, the existence of …

We employ radio-frequency spectroscopy to investigate a polarized spin mixture of ultracold
Li 6 atoms close to a broad Feshbach scattering resonance. Focusing on the regime of …