Phase-resolved nonlinear response of a two-dimensional electron gas under femtosecond intersubband excitation.
نویسندگان
چکیده
Strong electric-field transients resonant to intersubband transitions in n-type modulation-doped GaAs/AlGaAs quantum wells induce coherent Rabi oscillations, which are demonstrated by a phase-resolved measurement of the light emitted by the sample. The time evolution of the intersubband polarization is influenced by Coulomb-mediated many-body effects. The subpicosecond period and the phase of the Rabi oscillations are controlled by the properties of the midinfrared driving pulse.
منابع مشابه
Coherent nonlinear dynamics of intersubband excitations in a two-dimensional electron gas
Femtosecond midinfrared four-wave mixing is used to study the ultrafast dynamics of coherent intersubband polarizations in n-type modulation-doped GaAs/AlGaAs quantum wells. Time-integrated four-wave mixing yields a dephasing time of T2 1⁄4 320 fs; independent of excitation density. Time-resolved four-wave mixing unambiguously shows that the intersubband transition is purely homogeneously broad...
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ورودعنوان ژورنال:
- Physical review letters
دوره 92 4 شماره
صفحات -
تاریخ انتشار 2004