Other Condensed Matter
We consider population-imbalanced two-component Fermi gases under external harmonic confinement interacting through short-range two-body potentials with diverging s-wave scattering length. Using the fixed-node diffusion Monte Carlo method,…
We solve numerically for the first time the two-fluid, Hall--Vinen--Bekarevich--Khalatnikov (HVBK) equations for a He-II-like superfluid contained in a differentially rotating, spherical shell, generalizing previous simulations of viscous…
We study the effect of noise-induced dephasing on collisional phase-diffusion in the two-site Bose-Hubbard model. Dephasing of the quasi-momentum modes may slow down phase-diffusion in the quantum Zeno limit. Remarkably, the degree of…
We use supercomputer simulations to show that inter-atomic interactions can strongly affect the phase evolution of Bose-Einstein condensates that are diffracted from atom chips, thereby explaining recent experiments. Interactions broaden…
Electronic states with fractional spins arise in systems with large static correlation (strongly correlated systems). Such fractional-spin states are shown to be ensembles of degenerate ground states with normal spins. It is proven here…
We study the breathing mode frequencies of a rotating Fermi gas trapped in a harmonic plus radial quartic potential. We find that as the radial anharmonicity increases, the lowest order radial mode frequency increases while the next lowest…
The Letter analyzes stability of spin precession currents in superfluid $^3$He-B when the precession angle is very close to 104$^\circ$. In this limit a spin-precession vortex has a very large core, and a barrier blocking motion of these…
We report the observation of spin segregation, i.e., separation of spin density profiles, in a trapped ultracold Fermi gas of $^6$Li with a magnetically tunable scattering length close to zero. The roles of the spin components are inverted…
We have investigated the effects of tuning the localized surface plasmon resonances (LSPRs) of silver nanoparticles on the fluorescence intensity, lifetime, and Raman signal from nearby fluorophores. The presence of a metallic structure can…
Two-dimensional complexes of C_20 fullerenes connected to each other by covalent bonds have been studied. Several isomers with different types of intercluster bonds have been revealed. The lifetimes of the (C_20)_MxM systems with M = 2 and…
We control the current of a single particle quantum ratchet by designing ramping schemes for experimentally accessible control parameters. We harvest on Landau-Zener transitions between Floquet states. Adiabatic and diabatic ramping allow…
We present a theoretical analysis of the electron spin decoherence in single Nitrogen-Vacancy defects in ultra-pure diamond. The electron spin decoherence is due to the interactions with Carbon-13 nuclear spins in the diamond lattice. Our…
We report on measurements of the excitation spectrum of a strongly interacting Bose-Einstein condensate (BEC). A magnetic-field Feshbach resonance is used to tune atom-atom interactions in the condensate and to reach a regime where quantum…
A phase transition for bosonic atoms in a two-dimensional anisotropic optical lattice is considered. If the tunnelling rates in two directions are different, the system can undergo a transition between a two-dimensional superfluid and a…
Correlations of ambient seismic or acoustic vibrations are now widely used to reconstruct the impulse response between two passive receivers as if a source was placed at one of them. This provides the opportunity to do imaging without a…
Solid 4He has been created off the melting curve by growth at nearly constant mass via the "blocked capillary" technique and growth from the 4He superfluid at constant temperature. The experimental apparatus allows injection of 4He atoms…
Ground state energies for confined hydrogen (H) and helium (He) atoms, inside a penetrable/impenetrable compartment have been calculated using Diffusion Monte Carlo (DMC) method. Specifically, we have investigated spherical and ellipsoidal…
Spin-magnetophonon level splitting in a quantum well made of a semimagnetic wide gap semiconductor is considered. The semimagnetic semiconductors are characterized by a large effective $g$ factor. The resonance conditions $\hbar\omega_{\rm…
Effects of a periodic driving field on Landau-Zener processes are studied using a nonlinear two-mode model that describes the mean-field dynamics of a many-body system. A variety of different dynamical phenomena in different parameter…
We present a theory for a lattice array of weakly coupled one-dimensional ultracold attractive Fermi gases (1D `tubes') with spin imbalance, where strong intratube quantum fluctuations invalidate mean field theory. We first construct an…