We present a novel, simple asymptotic expansion for the spectrum of radiation that is backscattered from a laser by a counterpropagating (or copropagating) electron. The solutions are presented in such a way that they explicitly show the relative merit of using an intense laser and of an energetic electron beam in x-ray production in the single particle regime. Simple scaling laws are given.

We evaluate the low-temperature conductance of a weakly interacting one-dimensional helical liquid without axial spin symmetry. The lack of that symmetry allows for inelastic backscattering of a single electron, accompanied by forward scattering of another. This joint effect of weak interactions and potential scattering off impurities results in a temperature-dependent deviation from the quanti...

We demonstrate that electrostatic interactions between helical electrons at the edge of a quantum spin Hall insulator and dynamical impurity can induce quasi-elastic backscattering. Modelling as two-level system, we show transitions counterpropagating Kramers-degenerate electronic states occur without breaking time-reversal symmetry, provided also undergoes transition. The associated electrical...

Coupled theoretical and computational work is presented aimed at understanding and modeling stimulated Raman backscattering (SRBS) relevant to laser-plasma interactions (LPIs) in large-scale, nearly homogeneous plasmas. We address the following five observed, nonlinear phenomena associated with SRBS: coupling of SRBS to Langmuir decay interactions (LDIs); cascading of LDI; SRS cascades; and sti...