A Temperature Driven Hole-phonon Coupling Enhancement Effect in a Strongly Correlated 2D Hole System*

In strongly correlated 2D electron/hole system confined in semiconductor heterointerfaces, a pronounced non-monotonic behavior in the resistivty vs. temperature, ρ(T), has been widely observed when the system becomes quantum degenerate but no consensus has been reached regarding its origin. Here we report a study of the the hole-phonon coupling strength around the peak temperature T_p of the non-monotonic ρ(T) in a dilute 2D hole system with strong correlations by measuring the hot hole energy relaxation rate. The data can be well fitted by Bloch-Grüneisen theory of hole-phonon scattering but the deformational potential constant D shows a rapid change near T_P (around 6eV-12eV at high temperatures, T~T_F, the Fermi temperature, and around 30-80eV at low temperatures, T<<T_F). We suggest that these results could be related to the system being close to the transition into Wigner crystal state and compare them to the strong electron-phonon coupling effect in charge density wave states.