[9p-S422-1~13] 15.1 バルク結晶成長

▲ [9p-S422-8] Low temperature liquid phase growth and terahertz optical properties of 2D chalcogenide InSe crystal

〇Chao Tang¹、Yohei Sato¹、Katsuya Watanabe¹、Junya Osaki¹、Tadao Tanabe¹、Yutaka Oyama¹ (1.Tohoku Univ.)

キーワード：solution crystal growth, 2D material, Indium selenide

High quality InSe crystals have been successfully grown by temperature difference method under controlled vapor pressure (TDM-CVP) [1], which is a low temperature solution crystal growth approach allowing stoichiometry control via the application of selenium vapor pressure (Fig. 1). The optical properties in terahertz frequency range have been investigated using both the terahertz time domain spectroscopy (THz-TDS) and monochromatic terahertz spectroscopy via different frequency generation (DFG) process. It is shown that the absorption in terahertz range of InSe is far smaller than that of GaSe (Fig. 2). The Hall effect measurements are compared with the THz-TDS results in view of the carrier mobility and it is indicated that the estimation of carrier dynamics from THz spectroscopy is valid under some measurement conditions. The present study has clarified the potential of InSe to be applied as nonlinear optical crystal for THz generation.