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Related papers: Repulsive polarons in two-dimensional Fermi gases

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The Fermi-polaron problem of a mobile impurity interacting with fermionic medium emerges in various contexts, ranging from the foundations of Landau's Fermi-liquid theory to electron-exciton interaction in semiconductors, to unusual…

Quantum Gases · Physics 2021-11-02 Pavel E. Dolgirev , Yi-Fan Qu , Mikhail B. Zvonarev , Tao Shi , Eugene Demler

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 an ultracold atomic gas of $^{87}$Rb with a much lower density…

We provide an analytically tractable toy model of an infinitely heavy impurity interacting with the spin-polarized gas of bath fermions via a contact potential in 1D and placed in a harmonic trap. The solution to this problem requires…

Quantum Gases · Physics 2025-09-03 Nikolay Yegovtsev

We study the repulsive Fermi polaron in a two-component, two-dimensional system of fermionic atoms inspired by the results of a recent experiment with $^{173}$Yb atoms [N. Darkwah Oppong \textit{et al.}, Phys. Rev. Lett. \textbf{122},…

Quantum Gases · Physics 2021-04-14 Raúl Bombín , Viktor Cikojević , Juan Sánchez-Baena , Jordi Boronat

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

We study the attractive and repulsive two-component Fermi gas with spin imbalance in two dimensions. Using a generalized $T$-matrix approximation, we examine the thermodynamic properties of both attractive and repulsive contact interacting…

Quantum Gases · Physics 2014-08-15 Weiran Li

We analyze the dynamics of one-dimensional quantum gases with strongly attractive contact interactions. We specify a class of initial states for which attractive forces effectively act as strongly repulsive ones during the time evolution.…

Quantum Gases · Physics 2022-02-02 Maciej Łebek , Andrzej Syrwid , Piotr T. Grochowski , Kazimierz Rzążewski

We study the properties of an impurity of mass $M$ moving through a spatially homogeneous three-dimensional fully polarized Fermi gas of particles of mass $m$. In the weakly attractive limit, where the effective coupling constant $g\to0^-$…

Quantum Gases · Physics 2015-06-16 Christian Trefzger , Yvan Castin

We investigate the Fermi polaron problem in a spin-1/2 Fermi gas in an optical lattice for the limit of both strong repulsive contact interactions and one dimension. In this limit, a polaronic-like behaviour is not expected, and the physics…

Quantum Gases · Physics 2017-07-11 C. W. Duncan , F. F. Bellotti , P. Öhberg , N. T. Zinner , M. Valiente

We study in three dimensions the problem of a spatially homogeneous zero-temperature ideal Fermi gas of spin-polarized particles of mass $m$ perturbed by the presence of a single distinguishable impurity of mass $M$. The interaction between…

Quantum Gases · Physics 2015-06-19 Christian Trefzger , Yvan Castin

When dressed particles (polarons) exchange quantum phonons, the resulting interactions are generally attractive. If the particles have hard-core statistics and the coupling to phonons is through the kinetic energy terms, phonon-mediated…

Quantum Gases · Physics 2018-01-03 John Sous , Mona Berciu , Roman V. Krems

We show that the motion of spin-polarized impurity (ferron) in ultracold atomic gas is characterized by a certain critical velocity which can be traced back to the amount of spin imbalance inside the impurity. We have calculated the…

Quantum Gases · Physics 2025-06-30 Piotr Magierski , Buğra Tüzemen , Gabriel Wlazłowski

We study the impurity problem in a Fermi gas of $^{173}$Yb atoms near an orbital Feshbach resonance, where a single moving particle in the $^3P_0$ state interacting with two background Fermi seas of particles in different nuclear states of…

Quantum Gases · Physics 2018-01-30 Jin-Ge Chen , Yue-Ran Shi , Xiang Zhang , Wei Zhang

We investigate the phase diagram of a two-component repulsive Fermi gas at T=0 by means of quantum Monte Carlo simulations. For a given value of the positive s-wave scattering length, both purely repulsive and purely attractive model…

Quantum Gases · Physics 2015-05-18 S. Pilati , G. Bertaina , S. Giorgini , M. Troyer

These lecture notes give a brief introduction to the so-called Fermi-polaron problem, which explores the behaviour of a mobile impurity introduced into an ideal Fermi gas. While this problem has been considered now for more than a decade in…

Quantum Gases · Physics 2026-01-30 Meera M. Parish , Jesper Levinsen

We investigate the zero-temperature ferromagnetic behavior of a two-component repulsive Fermi gas in the presence of a correlated random field that represents an optical speckle pattern. The density is tuned so that the (noninteracting)…

Quantum Gases · Physics 2016-07-12 S. Pilati , E. Fratini

Impurities in a Fermi sea, or Fermi polarons, experience a Casimir interaction induced by quantum fluctuations of the medium. When there is short-range attraction between impurities and fermions, also the induced interaction between two…

We construct a variational wave function to study whether a fully polarized Fermi sea is energetically stable against a single spin flip. Our variational wave function contains sufficient short-range correlation at least to the same level…

Quantum Gases · Physics 2010-04-15 Xiaoling Cui , Hui Zhai

We study the quantum dynamics of a homogeneous ideal Fermi gas coupled to an impurity particle on a three-dimensional box with periodic boundary condition. For large Fermi momentum $k_\text{F}$, we prove that the effective dynamics is…

Mathematical Physics · Physics 2025-01-15 Duc Viet Hoang , Peter Pickl

We predict the phase separations of two-dimensional Fermi gases with repulsive contact-type interactions between two spin components. Using density-potential functional theory with systematic semiclassical approximations, we address the…