Functional renormalization for trion formation in ultracold fermion gases

Abstract

The energy spectrum for three species of identical fermionic atoms close to a Feshbach resonance is computed by use of a nonperturbative flow equation. Already a simple truncation shows that for large scattering length $|a|$ the lowest energy state is a "trion" (or trimer) bound state of three atoms. At the location of the resonance, for $|a|\to \infty$, we find an infinite set of trimer bound states, with exponentially decreasing binding energy. This feature was pointed out by Efimov. It arises from limit cycle scaling, which also leads to a periodic dependence of the three body scattering coupling on $\ln |a|$. Extending our findings by continuity to nonzero density and temperature we find that a "trion phase" separates a BEC and a BCS phase, with interesting quantum phase transitions for T=0.

9 pages, 4 figures, minor changes, reference added

References in corpus (26)

• Exact evolution equation for the effective potential
• Non-Perturbative Renormalization Flow in Quantum Field Theory and Statistical Physics
• Universality in Few-body Systems with Large Scattering Length
• Aspects of the Functional Renormalisation Group
• Renormalization of the Three-Body System with Short-Range Interactions
• Optimisation of the exact renormalisation group
• Exact Renormalization Group Equations. An Introductory Review
• The Three-Boson System with Short-Range Interactions
• Collisional stability of a three-component degenerate Fermi gas
• Precise determination of ${}^6$Li cold collision parameters by radio-frequency spectroscopy on weakly bound molecules
• Three-body recombination in Bose gases with large scattering length
• Three-boson problem near a narrow Feshbach resonance
• Color Superfluidity and "Baryon" Formation in Ultracold Fermions
• Renormalization Flow of Bound States
• Analytical solution of the bosonic three-body problem
• Superfluidity and magnetism in multicomponent ultracold fermions
• Effective average action in statistical physics and quantum field theory
• Flow Equations for the BCS-BEC Crossover
• BCS pairing in Fermi systems with several flavors
• Trionic phase of ultracold fermions in an optical lattice: A variational study
• Particle-hole fluctuations in the BCS-BEC Crossover
• Pairing in a three component Fermi gas
• Superfluidity in a Three-flavor Fermi Gas with SU(3) Symmetry
• Three-body scattering from nonperturbative flow equations
• Superfluidity in Three-species Mixture of Fermi Gases across Feshbach Resonances
• Co-existence and shell structures of several superfluids in trapped three-component Fermi mixtures

Cited by in corpus (37)

• The nonperturbative functional renormalization group and its applications
• Fundamentals of the Exact Renormalization Group
• Exact flow equation for composite operators
• Ultracold atoms and the Functional Renormalization Group
• Polaronic atom-trimer continuity in three-component Fermi gases
• Functional renormalization group approach to the BCS-BEC crossover
• Population imbalance and pairing in the BCS-BEC crossover of three-component ultracold fermions
• Nonrelativistic inverse square potential, scale anomaly, and complex extension
• Efimov effect from functional renormalization
• Renormalization group study of the four-body problem
• New type of crossover physics in three-component Fermi gases
• Finite-Temperature Properties of Attractive Three-Component Fermionic Atoms in Optical Lattices
• Magnetism and domain formation in SU(3)-symmetric multi-species Fermi mixtures
• Pauli blocking effects and Cooper triples in three-component Fermi gases
• Three-body loss in lithium from functional renormalization
• Efimov states near a Feshbach resonance and the limits of van der Waals universality at finite background scattering length
• Three-Component Fermionic Atoms with Repulsive Interaction in Optical Lattices
• Renormalization group study of Bose polarons
• Functional Renormalization for Chiral and U_A(1) Symmetries at Finite Temperature
• The renormalisation group and nuclear forces
• Three-body correlations in a two-dimensional SU(3) Fermi gas
• Topological Susceptibility in Three-Flavor Quark Meson Model at Finite Temperature
• Trion and Dimer Formation of Three-Color Fermions
• U(3) artificial gauge fields for cold atoms
• Renormalization group, dimer-dimer scattering, and three-body forces
• Convergence of a renormalization group approach to dimer-dimer scattering
• Three-body crossover from a Cooper triple to bound trimer state in three-component Fermi gases near a triatomic resonance
• QCD-like phase diagram with Efimov trimers and Cooper pairs in resonantly interacting SU(3) Fermi gases
• Efimov physics from the functional renormalization group
• Universal behaviour of four-boson systems from a functional renormalisation group
• Dimensional crossover in ultracold Fermi gases from Functional Renormalisation
• Four-boson bound states from a functional renormalisation group
• Multi-body correlations in SU(3) Fermi gases
• Flow equation of functional renormalization group for three-body scattering problems
• Magnetic Field Dependence and Efimov Resonance Broadening in Ultracold Three-Body Recombination
• Deconfinement Phase Transition with External Magnetic Field in Friedberg-Lee Model
• Trion formation and ordering in the attractive SU(3) Fermi-Hubbard model