Polaron states of electrons in the anisotropic surface over liquid helium

Abstract

The energetics and transport properties of the polaron in the anisotropic surface over liquid helium are investigated. The localization radii and the energy of the ground and excited states are calculated using the variational method within the hydrodynamic model of the polaron. In particular, we have considered maximal anisotropy which corresponds to the system of electrons in quasi-one-dimensional channels over liquid helium. The polaron binding energy is found and the temperature for the polaron formation is estimated below 0.1 K. Solving the hydrodynamic equations for fluid velocities, the polaron mobilities along and across the channel are determined. The possibility of experimental observation of polarons by measuring the frequency of spectroscopic transitions as well the mobility as functions of the holding electric field is addressed.

Electronic states above a helium film suspended on a ring-shaped substrate

“…The physical realization of Q1D electron systems over liquid helium allowed us to study different phenomena, such as transport properties, plasmons, and polaronic states. [12][13][14] In these systems, the charge carriers can move only in one spatial direction due to lateral confinement. Such confinement leads to a lateral potential introducing a new spatial quantization leading to a multisubband electron system.…”

Polaron effects in electron channels on a helium film

“…7 Quite recently 1D confinement effects on surface electrons on bulk helium have been addressed by using the hydrodynamic model of the polaron which describes the energetics of the dimple formation on the surface of liquid helium and its transport properties. 8 Even though surface excitations of the liquid helium film have in general a complicated dispersion relation coming from contributions of surface tension, gravity and film thickness, in the case of thin films the ripplon spectrum has a well-defined acoustical character. 5 In a previous work, 9 the 3D acoustical polaron was studied within the Feynman approach and it was found that, as a function of the electron-phonon coupling constant α, the polaron undergoes a self-trapping transition at α ∼ √ k 0 , where k 0 is a finite Debye cutoff in phonon space, which is continuous for k 0 < 18 and becomes discontinuous when k 0 > 18.…”