Spectroscopic verification of nanometer-spaced modulated structure that T1 compound which is a candidate for a thermoelectric material shows

利用T1LIII X射线荧光全息术重建了单晶T1InSe2热电材料中处于非公度（IC）相T1原子周围的三维原子像。实验获得的3D图像与理论计算的比较表明，T1原子具有非常大的空间波动，这与该材料的IC相有关，并且与理论声子计算所提出的那些相对应。此外，我们还用角分辨光电子能谱（ARPES）观察到了T1GaTe_2和T1Se的十字型特殊色散结构。我们假设所观察到的奇特的色散结构是由高位表面导带的色散引起的，并且ARPES检测到了联合态密度。

Three dimensional(3D) atomic images around the T1 atoms in single crystal T1InSe_2 thermoelectric material in the incommensurate(IC) phase were reconstructed using T1LIII X-ray fluorescence holography. Comparison of the experimentally obtained 3D images with the theoretical calculated ones suggests that the T1 atoms have extremely large spatial fluctuations, which are related to the IC phase of this material, and corresponds well to those proposed by theoretical phonon calculations. Furthermore, we observed a cross-type peculiar dispersive structure for T1GaTe_2 and T1Se by means of angle-resolved photoemission spectroscopy(ARPES). It is assumed that the observed peculiar dispersive structure is caused by the dispersion of high-lying surface conduction bands and that ARPES detects the joint density of states.