講演情報
[14p-K508-10]Second harmonic generation of Bloch-type optical skyrmion
〇(P)Sushanta Kumar Pal1, A. Srinivasa Rao1, Hiroko Yokota2, Takashige Omatsu1 (1.Chiba Univ., 2.Inst. of Science Tokyo)
キーワード：
Optical skyrmion、Second Harmonic Generation、Optical Vortex
Optical skyrmions, which possess all possible polarization states mapped on a three-dimensional Poincaré sphere in a two-dimensional physical space, have been studied as emerging structured light fields. The optical skyrmions are promising to develop new fundamentals and advanced applications, such as exotic light-matter interactions, high-resolution imaging, and information processing. In this presentation, we demonstrate, for the first time to the best of our knowledge, the second harmonic generation of Bloch-type optical skyrmion. A picosecond laser (wavelength: 1064 nm, pulse width: 10 ps, pulse repetition frequency: 1 MHz) was used and its output was converted into a Bloch-type optical skyrmion by employing a Mach-Zehnder-type polarization interferometer. The generated optical skyrmion exhibited a top-hat-shaped spatial intensity profile and a skyrmion number of 0.79. The optical skyrmion was then focused onto a nonlinear BBO crystal with a thickness of 1 mm. The second harmonics showed an elliptical spot with minor and major axes about 1/6 and 1/3 of the fundamental spot diameter, indicating its super-resolution property. This super-resolution property of the frequency-doubled optical skyrmion will provide the potential to develop a high spatial resolution second harmonics microscope.