[14p-P10-1~25] Joint Session K "Wide bandgap oxide semiconductor materials and devices"（Poster）

[14p-P10-15] Excitonic emission in β-TlInS₂

〇(DC)RAUL RAMOS PAUCAR¹, Kazuki Kazuki¹, YongGu Shim², Alekperov Oktay³, Nazim Mamedov³ (1.Chiba Institute of Technology, 2.Osaka Prefecture University, 3.Institute of Physics, Azerbaijan National Academy of Sciences)

Keywords:Thallium-based ternary compounds, layered semiconductor, photoluminescence

Quasi-two-dimensional ternary thallium dichalcogenide TlInS₂ is well known as a layered semiconductor with interesting electrical, opticals, and structural properties which show potential for optoelectronic applications. It has been established that, on cooling, TlInS₂ compounds exhibits a sequence of structural phase transitions from a paraelectric-normal (N) phase to a ferroelectric-commensurate (C) phase via an intermediate incommensurate (I) phase. However, despite the fact that a large number of investigations have studies the physical properties of layered TlInS₂ crystals, the mechanisms which lead to the occurrence of these phase transitions is not completely clear, in part because of the existence of the different kind of polytypes. In this work, photoluminescence (PL) spectrum at the band edge region in the β-TlInS₂ crystals measured using a confocal microscopy system were investigated over the temperature range 77- 300 K, which includes the range of the successive phase transitions.Based on the analysis of the excitation intensity dependence of the PL intensity emission, we report the possible existence of exciton and biexciton structures.