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Related papers: Polaron in a non-abelian Aubry-Andr\'e-Harper mode…

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In this work, we explore the polaron and molecule physics by utilizing a unified variational ansatz with up to two particle-hole(p-h) excitations(V-2ph). We confirm the existence of a first-order transition in 3D and 2D Fermi polarons, and…

Quantum Gases · Physics 2021-06-23 Cheng Peng , Ruijin Liu , Wei Zhang , Xiaoling Cui

We investigate the highly polarized limit of a two-dimensional (2D) Fermi gas, where we effectively have a single spin-down impurity atom immersed in a spin-up Fermi sea. By constructing variational wave functions for the impurity, we map…

Quantum Gases · Physics 2013-04-30 Meera M. Parish , Jesper Levinsen

An extremely polarized mixture of an ultracold Fermi gas is expected to reduce to a Fermi polaron system, which consists of a single impurity immersed in the Fermi sea of majority atoms. By developing a many-body T -matrix theory, we…

Quantum Gases · Physics 2018-07-10 Hiroyuki Tajima , Shun Uchino

We investigate the properties of an impurity immersed in an ensemble of spin-polarized fermions confined in a tight quantum wire. We use a non-perturbative variational approach that accounts for virtual transverse excitations and…

Quantum Gases · Physics 2025-09-08 Lovro Anto Barišić , Giuliano Orso , Frédéric Chevy , Kris Van Houcke

Ultracold Fermi gases with tuneable interactions represent a unique test bed to explore the many-body physics of strongly interacting quantum systems. In the past decade, experiments have investigated a wealth of intriguing phenomena, and…

A two-dimensional spin-up ideal Fermi gas interacting attractively with a spin-down impurity in the continuum undergoes, at zero temperature, a first-order phase transition from a polaron to a dimeron state. Here we study a similar system…

Strongly Correlated Electrons · Physics 2025-09-16 Gerard Pascual , Jordi Boronat , Kris Van Houcke

The notion of a polaron, originally introduced in the context of electrons in ionic lattices, helps us to understand how a quantum impurity behaves when being immersed in and interacting with a many-body background. We discuss the impact of…

Quantum Gases · Physics 2021-04-16 Hiroyuki Tajima , Junichi Takahashi , Simeon I. Mistakidis , Eiji Nakano , Kei Iida

Polaron, a typical quasi-particle that describes a single impurity dressed with surrounding environment, serves as an ideal platform for bridging few- and many-body physics. In particular, different few-body correlations can compete with…

Quantum Gases · Physics 2024-10-29 Ruijin Liu , Xiaoling Cui

We investigate the zero-temperature quasiparticle properties of a mobile impurity immersed in a strongly interacting Fermi superfluid at the crossover from a Bose-Einstein condensate (BEC) to a Bardeen--Cooper--Schrieffer (BCS) superfluid,…

Quantum Gases · Physics 2022-02-18 Hui Hu , Jia Wang , Jing Zhou , Xia-Ji Liu

The dynamics of a single impurity in an environment is a fundamental problem in many-body physics. In the solid state, a well-known case is an impurity coupled to a bosonic bath, for example lattice vibrations. Here the impurity together…

We explore a new variational principle for studying one-dimensional quantum systems in a trapping potential. We focus on the Fermi polaron problem, where a single distinguishable impurity interacts through a contact potential with a…

Quantum Gases · Physics 2019-08-09 E. J. Lindgren , R. E. Barfknecht , N. T. Zinner

We develop a non-Gaussian variational approach that enables us to study both equilibrium and far-from-equilibrium physics of the two-dimensional Fermi polaron. This method provides an unbiased analysis of the polaron-to-molecule phase…

Quantum Gases · Physics 2026-05-01 Yi-Fan Qu , Pavel E. Dolgirev , Eugene Demler , Tao Shi

The ground state of an impurity immersed in a Fermi sea changes from a polaron to a molecule as the interaction strength is increased. We show here that the coupling between these two states is strongly suppressed due to a combination of…

Quantum Gases · Physics 2010-07-09 G. M. Bruun , P. Massignan

Polarons are among the most fundamental quasiparticles emerging in interacting many-body systems, forming already at the level of a single mobile dopant. In the context of the two-dimensional Fermi-Hubbard model, such polarons are predicted…

When mobile impurities are introduced and coupled to a Fermi sea, new quasiparticles known as Fermi polarons are formed. There are two interesting, yet drastically different regimes of the Fermi polaron problem: (I) the attractive polaron…

In this work we provide a comprehensive review of theoretical and experimental studies of the properties of polarons formed by mobile impurities strongly interacting with quantum many-body systems. We present a unified perspective on the…

Impurities immersed in hard-core Bose gases offer exciting opportunities to explore polaron and bipolaron physics. We investigate the ground state properties of a single and a pair of impurities throughout the superfluid and insulating…

Quantum Gases · Physics 2025-12-02 G. A. Domínguez-Castro , L. Santos , L. A. Peña Ardila

The three band p-d model of strongly correlated electrons interacting with optical phonon via diagonal and off-diagonal electron-phonon interaction is considered within cluster perturbation theory. At first step the exact diagonalization of…

Strongly Correlated Electrons · Physics 2015-11-04 I. A. Makarov , E. I. Shneyder , P. A. Kozlov , S. G. Ovchinnikov

We revisit the polaron-molecule transition in three-dimensional(3D) fermion systems using the well-established variational approach. The molecule is found to be intrinsically unstable against lowest-order particle-hole excitations, and it…

Quantum Gases · Physics 2021-01-04 Xiaoling Cui

We study an impurity atom in a two-dimensional Fermi gas using variational wave functions for (i) an impurity dressed by particle-hole excitations (polaron) and (ii) a dimer consisting of the impurity and a majority atom. In contrast to…

Quantum Gases · Physics 2011-02-22 Sascha Zöllner , G. M. Bruun , C. J. Pethick