Presentation Information
[9a-PA4-5]Stochastic Behavior of Local Photoisomerization in Photochromic Microcrystals
〇Akinobu Mochizuki1, Koyo Ueno1, Kingo Uchida2, Hirokazu Hori1, Kazuharu Uchiyama1 (1.Univ. of Yamanashi, 2.Ryukoku Univ)
Keywords:
photoisomerization,photochromism,scanning tunneling microscope
We investigated photoisomerization in photochromic diarylethene microcrystals toward highly integrated nano-optoelectronic devices inspired by biological parallel processing and memory effects. Diarylethene reversibly switches between open- and closed-ring isomers under visible or UV light. In this study, microcrystal arrays were prepared on platinum films, and suitable crystals were locally excited using a gold-coated metallic probe. The resulting nanoscale photoisomerized structures inside the crystals were evaluated not by optical microscopy but by scanning tunneling microscopy through local electronic-state measurements. By repeatedly inducing nanostructure formation through local excitation and erasing it with UV light at the same position in the same crystal, we examined the stochastic nature, reproducibility, and history dependence of pattern formation, including effects of crystal shape and molecular orientation.