Coherent control of two-photon-induced photocurrents in semiconductors with frequency-dependent response

Abstract

In this paper, two-photon (TP)-induced photocurrents in two different semiconductor diodes were coherently controlled simultaneously via phase-only shaping of femtosecond pulses. Because of their distinct TP absorption (TPA) spectral responses, the diodes generated noticeably different photocurrent yields depending on the pulse shape. By adjusting second- and third-order dispersion coefficients, we demonstrated that the yield contrast is enhanced when excited by the pulse, whose second-harmonic (SH) spectrum has a peak around the spectral range where those TPA spectral responses differ widely. Also, the photocurrent yield ratio was maximized or minimized using an optimization algorithm, with extremes corresponding to 1.20 and 0.75, respectively. Finally, it was demonstrated that different traces can result when autocorrelation (AC) functions of identical pulses are measured by those diodes with distinct TPA spectral responses.