[13p-2R-1~11] 9.5 New functional materials and new phenomena

[13p-2R-6] Temperature dependence of polarized Raman scattering spectra of TlInS₂

〇(DC)RAUL PAUCAR¹, YongGu Shim², Kazuki Wakita¹, Oktay Alekperov³, Nazim Mamedov³ (1.Chiba Inst. of Tech., 2.Osaka Pref. Univ., 3.Azerbaijan Inst. of Phys.)

Keywords:Ternary thallium chalcogenide,Raman scattering,Phase transition

TlInS₂ belongs to the group of ternary thallium dichalcogenides compounds with chemical formula TlMeX₂ (where Me = In or Ga, X = Se, S, or Te). They have both layered (TlInS₂, TlGaS₂, TlGaSe₂) and chain (TlInSe₂, TlInTe₂, TlGaTe₂) structures. These compounds attract particular interest due to high degree of anisotropy in their physical properties and potential applications in optoelectronics as well. In this work, the polarized Raman spectra of layered TlInS₂ crystals are reported. The optical phonons which shows strong temperature dependence are identified as interlayer vibrations and are related to the phase transition, while the phonons which show a weak temperature dependence are identified as intralayer vibrations. Furthermore, we present a preliminary assignment of the symmetry modes.