相关论文: Collective modes in multiband superfluids and supe…
We examine the dynamics of a Bose-Einstein condensate in a symmetric double-well potential for a broad range of non-linear couplings. We demonstrate the existence of a region, beyond those of Josephson oscillations and self-trapping, which…
Excitation mechanisms for collective waves in confined dense one-dimensional microfluidic droplet arrays are investigated by experiments and computer simulations. We demonstrate that distinct modes can be excited by creating specific…
An indispensable ingredient for pair density wave (PDW) superconductivity is the presence of an attractive pairing interaction at finite momentum. Here, we show how this condition can be met with straightforward electron-density…
In general a superconducting state breaks multiple symmetries and, therefore, is characterized by several different coherence lengths $\xi_i$, $i=1,...,N$. Moreover in multiband material even superconducting states that break only a single…
Driven systems are of fundamental scientific interest, as they can exhibit properties that are radically different from the same system at equilibrium. In certain cases, long-lived states of driven matter can emerge, which exhibit new…
Using a two-orbital model of the superconducting phase of the pnictides, we compute the spectrum of the Leggett mode -- a collective excitation of the phase of the superconducting gap known to exist in multi-gap superconductors -- for…
We show that a clean multiband superconductor may display one or several phase transitions with increasing temperature from or to frustrated configurations of the relative phases of the superconducting order parameters. These transitions…
In contrast to single-component superconductors, which are described at the level of Ginzburg-Landau theory by a single parameter \kappa and are divided in type-I \kappa<1/\sqrt{2} and type-II \kappa>1/\sqrt{2} classes, two-component…
Three structural populations with distinct average mobility are identified within an equilibrium two-dimensional Lennard-Jones fluid simulated via molecular dynamics at a constant temperature and varying density. Quantifying the structure…
Superconductors are the only experimentally accessible systems with spontaneously broken gauge symmetries which support topologically nontrivial defects, namely string defects. We propose two experiments whose aim is the observation of the…
We explore the physics of three-dimensional shell-shaped condensates, relevant to cold atoms in "bubble traps" and to Mott insulator-superfluid systems in optical lattices. We study the ground state of the condensate wavefunction,…
Recently, a three-component Ginzburg-Landau (GL) model compatible with the 3Q pair-density-wave state has been proposed to explain the fractional quantum magnetic resistance oscillations of period $\phi_0/3 = hc/6e$ observed in…
Lifshitz invariant is a symmetry invariant composed of multiple order parameters that contain a single spatial derivative in a Ginzburg-Landau (GL) free energy, which may induce a nonuniform configuration of the order parameters. In…
Order parameter collective modes are the fingerprint of a condensed phase. The spectroscopy of these modes in superfluid $^3$He and unconventional superconductors can provide key information on the symmetry of the condensate as well as the…
Taking account of a collective mode relevant to charge fluctuation, the optical conductivity of spin-density-wave state has been examined for an extended Hubbard model with one-dimensional quarter-filled band. We find that, within the…
Dynamical supersymmetry breaking is considered in models which admit descriptions in terms of electric, confined, or magnetic degrees of freedom in various limits. In this way, a variety of seemingly different theories which break…
The Raman response in a superconductor is a powerful probe to investigate the symmetry of the superconducting gap. Here we show that in a multiband superconductor it also offers the unique opportunity to establish if the driving pairing…
Motivated by the recent observation of the time-reversal symmetry broken state in K-doped BaFe$_2$As$_2$ superconducting alloys, we theoretically study the collective modes and the short time dynamics of the superconducting state with…
The ability to support metastable current-carrying states in multiply-connected settings is one of the prime signatures of superfluidity. Such states are investigated theoretically for the case of trapped Bose condensed alkali gases,…
A unitary Fermi gas has a surprisingly rich spectrum of large amplitude modes of the pairing field alone, which defies a description within a formalism involving only a reduced set of degrees of freedom, such as quantum hydrodynamics or a…