Spin-orbit interaction enhanced polaron effect in two-dimensional semiconductors

It is shown that in two-dimensional semiconductors, the electron-phonon interaction and polaronmass correction are both significantly enhanced by the Rashba spin-orbit coupling. The masscorrection is positive for the upper Rashba branch and negative for the lower Rashba branch. BothRashba branches have the same polaron binding energy, which is higher than that for systems in theabsence of spin-orbit interaction. To the leading order, the correction to the binding energy isproportional to the square of the spin-orbit coupling strength.