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

[18a-Z06-7] Measurement of the waveform of a mid-infrared near-field on a metal tip by using ultrafast modulation of photoemission current

〇Yusuke Arashida¹, Ippo Igarashi¹, Masashi Ishikawa¹, Shoji Yoshida¹, Osamu Takeuchi¹, Hidemi Shigekawa¹ (1.Univ. of Tsukba)

Keywords:Scanning tunneling microscopy, Mid-infrared, near field

We suceeded in measuring the tempral shape of a tip-enhanced mid-infrared near-field by using a pump-probe method. The light souce is the output of a optical parametric chirped pulse amprifier (OPCPA) with the pulse duration of 8.5 fs. The sub-cycle mid-infrared pulses were generetad by using optical rectification with a 30 µm GaSe crystal. We observed the pulse duration of mid-infrared pulses was 53 fs. The mid-infrared pulses are expected to improbe the temporal resolution of field-driven scanning tunneling microscopy.