[7a-PA4-1~6] 3.6 Ultrashort-pulse and high-intensity lasers

△ [7a-PA4-4] Plasmonic enhancement of mid-IR fields and photoemission at a tungsten nanotip

〇(M2)Kengo Takeuchi¹, Tomoya Mizuno¹, Keisuke Kaneshima¹, Teruto Knai¹, Nobuhisa Ishii¹, Jiro Itatani¹ (1.Tokyo Univ.,ISSP)

Keywords:nanotip, strong field photoemission, near field

We investigate photoemission from a tungsten nanotip by mid-IR pulses. To deeply understand the photoelectron spectra, we estimate the spatial distribution of photoelectric field by solving the FDTD method. Then we measure the wavelength-dependence and calculate the photoelectron kinetic energy within the classical mechanism. As a result, we reveal that the enhancement factor increases as the wavelength increases.