其他凝聚态物理
We simulate the growth of a dual species Bose-Einstein condensate using a Gross-Pitaevskii equation with an additional gain term giving rise to the growth. Such growth occurs during simultaneous evaporative cooling of a mixture of two…
The non-linear zero-differential resistance state (ZDRS) that occurs for highly mobile two-dimensional electron systems in response to a dc bias in the presence of a strong magnetic field applied perpendicular to the electron plane is…
A Bose-Einstein condensate produced by a Hamiltonian which is rotationally or translationally symmetric is fragmented as a direct result of these symmetries. A corresponding mean-field unfragmented state, with an identical energy to leading…
Spatiotemporal correlations of the one-dimensional spring-block (Burridge-Knopoff) model of earthquakes, either with or without the viscosity term, are studied by means of numerical computer simulations. The continuum limit of the model is…
Nanoscale optoelectronics and molecular-electronics systems operate with current injection and nonequilibrium tunneling, phenomena that challenge consistent descriptions of the steady-state transport. The current affects the…
The advantage of Bridgman anvil pressure cells is their wide pressure range and the large number of wires which can be introduced into the pressure chamber. In these pressure cells soft solid pressure mediums like steatite are used. We have…
We develop a systematic analytical approach to study the linear and nonlinear solitary excitations of quasi-one-dimensional Bose-Einstein condensates trapped in an optical lattice. For the linear case, the Bloch wave in the $nth$ energy…
High energy resolution photoelectron spectroscopy of conduction electrons in the vicinity of the Fermi-edge in Al and Au at the excitation energy of 880 and 7940 eV was carried out using synchrotron radiation. For the excitation energy of…
A set of weakly interacting spin-1/2 Fermions, confined by a harmonic oscillator potential, and interacting with each other via a contact potential, is a model system which closely represents the physics of a dilute gas of two-component…
We apply an analytical model for anisotropic, colliding Bose-Einstein condensates in a spontaneous four wave mixing geometry to evaluate the second order correlation function of the field of scattered atoms. Our approach uses quantized…
The low-lying eigenstates of a one-dimensional (1D) system of many impenetrable point bosons and one moving impurity particle with repulsive zero-range impurity-boson interaction are found for all values of the impurity-boson mass ratio and…
The field of few-body physics has originally been motivated by understanding nuclear matter. New model systems to experimentally explore few-body quantum systems can now be realized in ultracold gases with tunable interactions. Albeit the…
The excitation spectrum around the pump-only stationary state of a polariton optical parametric oscillator (OPO) in semiconductor microcavities is investigated by time-resolved photoluminescence. The response to a weak pulsed perturbation…
We study the dynamics of strongly correlated one-dimensional Bose gases in a combined harmonic and optical lattice potential subjected to sudden displacement of the confining potential. Using the time-evolving block decimation method, we…
We study the effect of confinement on solid 4-He's nonclassical rotational inertia (NCRI) in a torsional oscillator by constraining it to narrow annular cells of various widths. The NCRI exhibits a broad maximum value of 20% for annuli of…
Recently, an effective non-Abelian magnetic field with a topology of a monopole was shown to emerge from the adiabatic motion of multilevel atoms in spatially varying laser fields [J. Ruseckas et al., Phys. Rev. Lett. 95, 010404 (2005)]. We…
The specific heat of liquid helium was calculated theoretically in the Landau theory. The results deviate from experimental data in the temperature region of 1.3 - 2.1 K. Many theorists subsequently improved the results of the Landau theory…
We theoretically investigate the effect of an anisotropic trap on the instability of the polar $(m_F=0)$ phase of a spin-1 Bose-Einstein condensate. By considering rigorously the spatial quantization, we show that the growth of the nascent…
We study the van der Waals frictional drag force induced by liquid flow in low-dimensional systems (2D and 1D electron systems, and 2D and 1D channels with liquid). We find that for both 1D and 2D systems, the frictional drag force induced…
On the ground of the Landau criterion we study the behavior of critical velocities in a superfluid two-component Bose gas. It is found that under motion of the components with different velocities the velocity of each component should not…