Related papers: Free at Last: Bose Metal Uncaged
The conventional theory of metals is in crisis. In the last 15 years, there has been an unexpected sprouting of metallic states in low dimensional systems directly contradicting conventional wisdom. For example, bosons are thought to exist…
I analyze the recent observation of a Bose metal in NbSe$_2$ and place these results in the wider context of the first sighting of such a phase in amorphous Bi and MoGe thin films.
In the quantum rotor model with random exchange interactions having a non-zero mean, three phases, a 1) phase (Bose) glass, 2) superfluid, and 3) Mott insulator, meet at a bi-critical point. We demonstrate that proximity to the bi-critical…
In this paper, we extend our previous discussion of the Bose metal to the field tuned case. We point out that the recent observation of the metallic state as an intermediate phase between the superconductor and the insulator in the field…
Two of the most prominent phases of bosonic matter are the superfluid with perfect flow and the insulator with no flow. A now decades-old mystery unexpectedly arose when experimental observations indicated that bosons could organize into…
This paper aims to justify, at a microscopic level, the existence of a two-dimensional Bose metal, i.e. a metallic phase made out of Cooper pairs at T=0. To this end, we consider the physics of quantum phase fluctuations in (granular)…
We show here that the regularization of the conductivity resulting from the bosonic interactions on the `insulating' (quantum disordered) side of an insulator-superconductor transition in 2D gives rise to a metal with a finite conductivity,…
Motivated by the recent experimental observation of an intermediate bosonic metallic state in the two-dimensional superconductor-insulator transition at $T=0$, we study an extended Bose Hubbard model in the limit of large number of…
Two-dimensional (2D) materials are not expected to be metals at low temperature due to electron localization. Consistent with this, pioneering studies on thin films reported only superconducting and insulating ground states, with a direct…
We revisit the concept of superfluidity in bosonic lattice models in low dimensions. Then, by using numerical and analytical results obtained previously for equivalent spinless fermion models, we show that the gapless phase of 1D…
Bose metals are metals made of Cooper pairs, which form at very low temperatures in superconducting films and Josephson junction arrays as an intermediate phase between superconductivity and superinsulation. We predicted the existence of…
A spin-wave approach of the zero temperature superfluid-insulator transition for two-dimensional hard-core bosons in a random potential $\mu=\pm$ W is developed. While at the classical level there is no intervening phase between the…
We consider the two dimensional disordered Bose gas which present a metallic state at low temperatures. A simple model of an interacting Bose system in a random field is propose to consider the interaction effect on the transition in the…
Destruction of superconductivity in thin films was thought to be a simple instance of Berezinskii-Kosterlitz-Thouless physics in which only two phases exist: a superconductor with algebraic long range order in which the vortices condense…
We study a two-dimensional system of bosons interacting with a fluctuating U(1) gauge field with overdamped dynamics. We find two instabilities of the condensed phase at T=0: one to phase separation and another to a homogeneous…
We study numerically a 2D Bose-Einstein condensate in a quasiperiodic array of potential peaks, assumed to be generated by superimposing five blue detuned laser beams. By using a Bogoliubov ansatz for the excitations we show that the system…
The emergence of quantum metallic state marked by a saturating finite electrical resistance in the zero-temperature limit in a variety of two-dimensional superconductors injects an exciting momentum to the realm of heterostructure…
We propose a characterization of zero temperature phases in disordered superconductors on the basis of the nature of quasiparticle transport. In three dimensional systems, there are two distinct phases in close analogy to the distinction…
After decades of explorations, suffering from low critical temperature and subtle nature, whether a metallic ground state exists in a two-dimensional system beyond Anderson localization is still a mystery. Supremely, phase coherence could…
A brief review of metal-insulator transitions in three-dimensional doped semiconductors, with emphasis on the "critical exponent puzzle"; and new experimental findings that signal the possibility of an unexpected metal-insulator transition…