Figure 1

Shape of the momentum distribution of the photoinduced electrons. In the case of excitation by linearly polarized light, the schematic diagram for carriers under the Gaussian light spot, and the photocurrent distribution in the light spot. (a) and (b) correspond to 1hh-1e and 1lh-1e transition, respectively. In both cases the symmetry axis of the alignment is along the polarization vector, e, of the exciting light. The lengths of the vectors indicate the populations of the states with the corresponding momentum directions. (c) A schematic diagram for carriers with momentum alignment under the Gaussian light spot. During the momentum relaxation time, carriers with opposite momentum directions have a small spatial displacement. (d) The photocurrent distribution in the light spot is proportional to the gradient of light intensity along the momentum alignment direction.