Electron-electron Umklapp process in two-dimensional electron gas under a spatially alternating magnetic field

We have studied the transport phenomenon in two-dimensional electron gas at a GaAs/AlGaAs heterointerface placed in a spatially alternating magnetic f ield. The effect of the periodic magnetic field is twofold. One is the effe ctive mass renormalization which manifests itself as resistivity enhancemen t in the T --> 0 limit. The other is a T-2-dependent relaxation rate which is attributed to the electron-electron Umklapp scattering. A similar phenom enon observed at, higher bias current, provides additional support to this interpretation and forms a basis for a new method of hot electron thermomet ry.