Asymptotic Field Dependence of Approach to Saturation of Drift Velocity of Electrons in Liquid Xenon

Abstract

Abstract The high electric field saturation drift velocity v sat of electrons in liquid xenon near the triple point is 3 × 103 m/s. This value is recovered if (Vsat d) κsat τsat =D. Here D is the self-diffusion coefficient of liquid xenon, τsat is the lower limit of phonon oscillation periods, and κsat is an electron energy-loss probability characteristic of scattering of field-driven electrons by the atoms of the liquid medium. Given the form of the saturation drift velocity, the asymptotic field (E) dependence of the approach to the drift velocity saturation is then explored by expanding κ(Eτ(E) in the form κ(Eτ(E) = κsat τsat + A 1/E γ + higher-order terms. From experimental results of Huang and Freeman, γ is found to be 4/3. This form cannot, of course, be extended into regimes of much lower electric field where a further physical mechanism contributes to the electron mobility.