Related papers: The Stark effect in superfluid $^4$He with relativ…
We present a simple quantum mechanical model describing excited rotational states of molecules in superfluid helium nanodroplets, as recently studied in non-adiabatic molecular alignment experiments [Cherepanov et al., Phys. Rev. A 104,…
Laser-assisted electron scattering (LAES), a light-matter interaction process that facilitates energy transfer between strong light fields and free electrons, has so far been observed only in gas phase. Here we report on the observation of…
We consider the vibrational energy levels of the first two electronic states of the molecule ion $H_2^+$. The Born-Oppenheimer method applied to the case of the Stark effect on a $H_2^+$-like molecule gives existence of sharp resonances…
We study the electron temperature profiles for an inhomogeneous electron flow in the hydrodynamic regime. We assume that the inhomogeneity is due to a weakly non-uniform distribution of the momentum relaxation time within a spherically…
Studies of atomic systems in electric fields are challenging because of the diverging perturbation series. However, physically meaningful Stark shifts and ionization rates can be found by analytical continuation of the series using…
We have performed a high resolution specific heat measurement on 4He completely filling the pores of Vycor glass. Within 10mK of the superfluid transition we have found a peak in the heat capacity which is only 0.02% the size of the…
Valuable dynamical and structural information about neat liquid DMSO at ambient conditions can be obtained through study of low frequency vibrations in the far infrared (FIR), that is, terahertz regime. For DMSO, collective excitations as…
Quantitative analyses of low-mass hydrogen-deficient (super-)giant stars - so-called extreme helium stars - to date face two major difficulties. First, theory fails to reproduce the observed helium lines in their entirety, wings and line…
We present a theoretical analysis of the acoustic radiation force on a single small particle, either a thermoviscous fluid droplet or a thermoelastic solid particle, suspended in a viscous and heat-conducting fluid medium. Our analysis…
We study nonlinear inter-subband microwave absorption of electrons bound to the liquid helium surface. Already for a comparatively low radiation intensity, resonant absorption due to transitions between the two lowest subbands is…
We report the first results on ultracold neutron production from a new spallation-driven superfluid $^4$He (He-II) source at TRIUMF, which is being prepared for a new, precise measurement of the neutron electric dipole moment. A total of…
Measurements of the order parameter texture of rotating superfluid 3He-B have been performed as a function of the applied azimuthal counterflow velocity down to temperatures of 0.2Tc. The results are compared to the hydrostatic theory of…
Using the semiclassical perturbation method, electron-, proton-, and ionized helium-impact line widths and shifts for the nine Cr I spectral lines from the $4p^7P^0-4d^7D$ multiplet, have been calculated for a perturbers density of…
We report on an unconventional $macroscopic$ field effect transistor composed of electrons floating above the surface of superfluid helium. With this device unique transport regimes are realized in which the charge density of the electron…
In this short note, we present some work on investigating electron temperatures and potentials in steady or unsteady dilute plasma flows. The analysis is based on the detailed fluid model for electrons. Ionization, normalized electron…
The linear Stark effect for the first excited state of the hydrogen atom shows that, in the unperturbed states, the atom has a permanent electric dipole moment (EDM) of magnitude 3eao (ao is Bohr radius). The EDM is not induce by the…
The experimental and theoretical study of the electrorheological (ER) effect observed in the nematic phase of the 4-n-hepthyl-4'-cyanobiphenyl (K21) is the aim of this work. The K21 liquid crystal (LC) appears to be a model system where all…
A theory accounting for the dynamical aspects of the superfluid response of one dimensional (1D) quantum fluids is reported. In long 1D systems the onset of superfluidity is related to the dynamical suppression of quantum phase slips at low…
The metastable Helium (He*) lines near $10830~{\rm A}$ are ideal probes of atmospheric erosion--a common phenomenon of close-in exoplanet evolution. A handful of exoplanet observations yielded well-resolved He* absorption features in…
We study the interaction of a fast moving particle in the Quark Gluon Plasma with linearized hydrodynamics. We derive the linearized hydrodynamic equations on top of an expanding fireball, and detail the solutions for a static medium. There…