[18a-Z06-1~11] 3.6 Ultrashort-pulse and high-intensity lasers

△ [18a-Z06-2] Observation of Rotational Doppler Shift in Harmonic Generation of Solids

〇Wataru Komatsubara¹, Kuniaki Konishi¹, Junji Yumoto¹, Makoto Kuwata-Gonokami¹ (1.Graduate school of Science, The Univ. of Tokyo)

Keywords:harmonic generation, solid, rotational doppler shift

Harmonic generation from solids with circularly polarized beam can be understood from the conservation laws of spin angular momentum (SAM) of the electric field and angular momentum of the material. In this process, the material receives the SAM of the electric field, but it is not excited and remains in the ground state since it receives the SAM as a torque. When the material with the poor symmetry receives the SAM, there will be two processes, but it has not been observed so far. In this study, the existence of two exchange processes of SAM between the electric field and the material was demonstrated for the first time by observing the rotational doppler shift.