Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

International Journal of Modern Physics B

SUPERFLUID TO BOSE METAL TRANSITION IN SYSTEMS WITH RESONANT PAIRING

J. Ranninger

Published Oct 20, 2008• 0 citations
Publisher

Abstract

Experiments in thin films whose thickness can be modified and by this way induce a superconductor to insulator transition, seem to suggest that in the quantum critical regime of this phase transition there might be a Bose metal, i.e., uncondensed bosonic carriers with a finite dissipation. This poses a fundamental problem as to our understanding of how such a state could be justified. On the basis of a simple Boson-Fermion model, where bosonic and fermionic degrees of freedom are strongly inter-related via a Boson-Fermion pair exchange coupling g, we illustrate how such a bosonic metal phase could possibly come about. We show that, as we approach the quantum critical point at some critical gc from the superfluid side, the superfluid phase locking is sustained only for longer and longer spatial scales. On a finite spatial scale, the boson have a quasi-free itinerant behavior with metallic features. At the quantum critical point the systems exhibits a phase separation which shows a ressemblance to that of a He 3– He 4 mixture. This could be the clue to the apparent dilemma of a Bose metal at zero temperature.

DOI
10.1142/s0217979208050139

Related papers

First-Order Transition from Superfluid to Bose-Metal State in Systems with Resonant Pairing

Tobias Stauber, J. Ranninger

Systems showing resonant superfluidity, driven by an exchange coupling of strength g between uncorrelated pairs of itinerant fermions and tightly bound ones, undergo a first-order phase transition as g increases beyond some critical value gc. The superfluid phase for g<or=gc is characterized by a gap in the fermionic single-particle spectrum and an acoustic sound-wave-like collective mode of the bosonic resonating fermion pairs inside this gap. For g>gc this state gives way to a phase-uncorrelated bosonic liquid with a q2 spectrum.

arXiv:0706.3143•Physical Review Letters•Jul 26, 2007•5 citations

Suppression of superfluidity by dissipation: An application to failed superconductors

Kou Misaki, Naoto Nagaosa

The ground states of bosons have been classified into superfluids, bosonic quantum Hall states, Mott insulators, and Bose glass. Recent experiments in two-dimensional clean superconductors under an external magnetic field $B$ strongly suggest the existence of the fourth quantum state of Cooper pairs, i.e., Bose metal or quantum metal, where the resistivity remains constant at lowest temperature. However, its theoretical understanding remains unsettled. In this paper, we propose a model where the vortices behave as quantum bosons subject to dissipation at the normal core. We discuss that those bosons remain metallic even at zero temperature by generalizing the Feynman picture of superfluidity in the first quantization formulation and also by a perturbative calculation for a field theoretical model in the second quantization formalism. This result indicates that the resistivity $\ensuremath{\rho}$ of Bose metal at zero temperature behaves as $\ensuremath{\rho}\ensuremath{\sim}{\ensuremath{\rho}}_{n}(B/{B}_{c2})$ with ${\ensuremath{\rho}}_{n}$ being the residual resistivity in the normal state and ${B}_{c2}$ the second upper critical field. It also predicts that the Bose metal is missing in superclean superconductors and at the dirty limit or in granular superconductors.

arXiv:1908.06590•Physical review. B./Physical review. B•Sep 30, 2020•0 citations

Possibility of a metallic phase in granular superconducting films

Tai Kai Ng, Derek K. K. Lee

We investigate the possibility of finding a zero-temperature metallic phase in granular superconducting films, modeled as a dissipative Bose system. We extend the conventional treatment of these systems to a formalism that can distinguish between insulator, metal, and superfluid phases. We do not find a metallic state at zero temperature. At finite temperatures, we find that the system exhibits a crossover between superfluid and metallic behavior. This has implications for the analysis of experimental results that makes use of a scaling hypothesis involving only a single parameter. We also investigate the effect of vortex dissipation in these systems.

arXiv:cond-mat/0007155•Physical review. B, Condensed matter•Mar 19, 2001•14 citations

Superconductor-Insulator Transition in a Non-Fermi Liquid

Alexander L. Chudnovskiy, Alex Kamenev

We present a model of a strongly correlated system with a non-Fermi liquid high temperature phase. Its ground state undergoes an insulator to superconductor quantum phase transition (QPT) as a function of a pairing interaction strength. Both the insulator and the superconductor are originating from the same interaction mechanism. The resistivity in the insulating phase exhibits the activation behavior with the activation energy, which goes to zero at the QPT. This leads to a wide quantum critical regime with an algebraic temperature dependence of the resistivity. Upon raising the temperature in the superconducting phase, the model exhibits a finite temperature phase transition to a Bose metal phase, which separates the superconductor from the non-Fermi liquid metal.

arXiv:2207.12307•Physical Review Letters•Dec 22, 2022•10 citations

Evidence for Metallic Behavior in an Atomic Bose-Hubbard System

David C. McKay, Matt White, Matthew Pasienski +1 more

We have observed a metallic-like state, which persists to the zerotemperature limit, in a 3D Bose-Hubbard system of ultra-cold atoms trapped in an optical lattice. The damping rate of atomic motion— the analog of electrical resistance in a solid—in the confining parabolic potential fits well to a model that includes finite damping at zero temperature. The low-temperature behavior is consistent with the theory of quantum tunneling of phase slips, while at higher temperatures a cross-over consistent with the transition between quantum tunneling and thermal activation of phase slips is evident. The existence of a metallic phase in a bosonic system may have implications for the unusual dissipative phases apparent in solid-state superconducting films. The ground state of a system of bosons is predicted to be either superconducting or insulating (1). However, experiments on superconducting films have shown that a dissipative phase can exist to the lowest temperatures attainable. For example, experiments on

•Aug 22, 2007•0 citations

Finite-temperature study of Bose-Fermi superfluid mixtures

B. Ramachandhran, S. G. Bhongale, Han Pu

Ultracold atom experiments offer the unique opportunity to study mixing of different types of superfluid states. Our interest is in superfluid mixtures comprising of particles with different statistics---Bose and Fermi. Such scenarios occur naturally, for example, in dense quantum chromodynamics (QCD) matter. Interestingly, cold atomic experiments are performed in traps with finite spatial extent, thus critically destabilizing the occurrence of various homogeneous phases. Critical to this analysis is the understanding that the trapped system can undergo phase separation, resulting in a unique situation where phase transition in either species (bosons or fermions) can overlap with the phase separation between possible phases. In the present work, we illustrate how this intriguing interplay manifests in an interacting two-species atomic mixture---one bosonic and another fermionic with two spin components---within a realistic trap configuration. We further show that such interplay of transitions can render the nature of the ground state to be highly sensitive to the experimental parameters and the dimensionality of the system.

arXiv:1102.1450•Physical Review A•Mar 10, 2011•15 citations
Experiments in thin films whose thickness can be modified and by this way induce a superconductor to insulator transition, seem to suggest that in the quantum critical regime of this phase transition there might be a Bose metal, i.e., uncondensed bosonic carriers with a finite dissipation. This poses a fundamental problem as to our understanding of how such a state could be justified. On the basis of a simple Boson-Fermion model, where bosonic and fermionic degrees of freedom are strongly inter-related via a Boson-Fermion pair exchange coupling g, we illustrate how such a bosonic metal phase could possibly come about. We show that, as we approach the quantum critical point at some critical gc from the superfluid side, the superfluid phase locking is sustained only for longer and longer spatial scales. On a finite spatial scale, the boson have a quasi-free itinerant behavior with metallic features. At the quantum critical point the systems exhibits a phase separation which shows a ressemblance to that of a He 3– He 4 mixture. This could be the clue to the apparent dilemma of a Bose metal at zero temperature.
Systems showing resonant superfluidity, driven by an exchange coupling of strength g between uncorrelated pairs of itinerant fermions and tightly bound ones, undergo a first-order phase transition as g increases beyond some critical value gc. The superfluid phase for g<or=gc is characterized by a gap in the fermionic single-particle spectrum and an acoustic sound-wave-like collective mode of the bosonic resonating fermion pairs inside this gap. For g>gc this state gives way to a phase-uncorrelated bosonic liquid with a q2 spectrum.
The ground states of bosons have been classified into superfluids, bosonic quantum Hall states, Mott insulators, and Bose glass. Recent experiments in two-dimensional clean superconductors under an external magnetic field BBB strongly suggest the existence of the fourth quantum state of Cooper pairs, i.e., Bose metal or quantum metal, where the resistivity remains constant at lowest temperature. However, its theoretical understanding remains unsettled. In this paper, we propose a model where the vortices behave as quantum bosons subject to dissipation at the normal core. We discuss that those bosons remain metallic even at zero temperature by generalizing the Feynman picture of superfluidity in the first quantization formulation and also by a perturbative calculation for a field theoretical model in the second quantization formalism. This result indicates that the resistivity $\ensuremath{\rho}$ of Bose metal at zero temperature behaves as $\ensuremath{\rho}\ensuremath{\sim}{\ensuremath{\rho}}_{n}(B/{B}_{c2})$ with ${\ensuremath{\rho}}_{n}$ being the residual resistivity in the normal state and Bc2{B}_{c2}Bc2​ the second upper critical field. It also predicts that the Bose metal is missing in superclean superconductors and at the dirty limit or in granular superconductors.
We investigate the possibility of finding a zero-temperature metallic phase in granular superconducting films, modeled as a dissipative Bose system. We extend the conventional treatment of these systems to a formalism that can distinguish between insulator, metal, and superfluid phases. We do not find a metallic state at zero temperature. At finite temperatures, we find that the system exhibits a crossover between superfluid and metallic behavior. This has implications for the analysis of experimental results that makes use of a scaling hypothesis involving only a single parameter. We also investigate the effect of vortex dissipation in these systems.
We present a model of a strongly correlated system with a non-Fermi liquid high temperature phase. Its ground state undergoes an insulator to superconductor quantum phase transition (QPT) as a function of a pairing interaction strength. Both the insulator and the superconductor are originating from the same interaction mechanism. The resistivity in the insulating phase exhibits the activation behavior with the activation energy, which goes to zero at the QPT. This leads to a wide quantum critical regime with an algebraic temperature dependence of the resistivity. Upon raising the temperature in the superconducting phase, the model exhibits a finite temperature phase transition to a Bose metal phase, which separates the superconductor from the non-Fermi liquid metal.
We have observed a metallic-like state, which persists to the zerotemperature limit, in a 3D Bose-Hubbard system of ultra-cold atoms trapped in an optical lattice. The damping rate of atomic motion— the analog of electrical resistance in a solid—in the confining parabolic potential fits well to a model that includes finite damping at zero temperature. The low-temperature behavior is consistent with the theory of quantum tunneling of phase slips, while at higher temperatures a cross-over consistent with the transition between quantum tunneling and thermal activation of phase slips is evident. The existence of a metallic phase in a bosonic system may have implications for the unusual dissipative phases apparent in solid-state superconducting films. The ground state of a system of bosons is predicted to be either superconducting or insulating (1). However, experiments on superconducting films have shown that a dissipative phase can exist to the lowest temperatures attainable. For example, experiments on
Ultracold atom experiments offer the unique opportunity to study mixing of different types of superfluid states. Our interest is in superfluid mixtures comprising of particles with different statistics---Bose and Fermi. Such scenarios occur naturally, for example, in dense quantum chromodynamics (QCD) matter. Interestingly, cold atomic experiments are performed in traps with finite spatial extent, thus critically destabilizing the occurrence of various homogeneous phases. Critical to this analysis is the understanding that the trapped system can undergo phase separation, resulting in a unique situation where phase transition in either species (bosons or fermions) can overlap with the phase separation between possible phases. In the present work, we illustrate how this intriguing interplay manifests in an interacting two-species atomic mixture---one bosonic and another fermionic with two spin components---within a realistic trap configuration. We further show that such interplay of transitions can render the nature of the ground state to be highly sensitive to the experimental parameters and the dimensionality of the system.