[14p-B2-1~19] 3.9 Terahertz technologies

△ [14p-B2-11] Sub-cycle optical modulation by using THz-photon-dressed excitonic state

〇Kento Uchida^1,2, Tomohito Otobe³, Toshimitsu Mochizuki⁴, Changsu Kim⁵, Masahiro Yoshita⁵, Hidefumi Akiyama⁵, Loren Pfeiffer⁶, Ken West⁶, Koichiro Tanaka^1,2, Hideki Hirori^1,7 (1.iCeMS, Kyoto Univ., 2.Dept. Phys. Kyoto Univ., 3.QST, 4.AIST, 5.ISSP, Univ. of Tokyo, 6.Princeton Univ., 7.JST-PRESTO)

Keywords:Intense Terahertz generation, Nonlinear THz spectroscopy, GaAs quantum well

We studied the role of the excitonic dressed state in the optical response by using phase-stable and strong THz transients as a driving field. We succeeded in demonstrating that the optical absorption of a GaAs quantum well can be modulated on a sub-cycle timescale of the THz fields. The measurements were in good agreement with the analytical formula considering the dressed state, indicating that the sideband emissions coherently reshapes the output optical intensity.