Interband Bloch oscillation mechanism for high-harmonic generation in semiconductor crystals
نویسندگان
چکیده
High harmonic generation in semiconductors is analyzed for high mid-infrared laser intensities for which the electron-hole pair is driven beyond the first Brillouin zone and exhibits Bloch oscillations. We find that even a two-band analysis exhibits second and higher plateaus. Whereas the first plateau is shown to be consistent with high harmonic generation through electron-hole recollision, the higher plateaus arise from dynamic Bloch oscillations; however, the driving process is interband in nature, in contrast to the generally accepted intraband Bloch oscillation mechanism. Energy conservation is fulfilled, as harmonics beyond the first plateau come from a cascaded nonlinearity.
منابع مشابه
Interband optical investigation of Bloch oscillations in semiconductor superlattices
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