Metal-insulator transition in thiospinel CuIr2S4

✍ Scribed by Shoichi Nagata; Takatsugu Hagino; Yoshitaka Seki; Teruo Bitoh

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 116 KB
• Volume: 194-196
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/0921-4526(94)90868-0

✦ Synopsis

We have discovered the existence of metal-insulator transition at ~220 K in the new thiospinel CuIr2S 4. The electrical conductivity, a, for sintered-powder specimens drops abruptly from 2×102 S,cm -1 to 5×10-1S'cm -1 at TM_I-~220 K with decreasing temperature. At temperatures T<TM_ I, CuIr2S 4 exhibits a semiconductive behavior with thermally activated conductivity, which is fitted by the formula: a : Aexp(-q/kBT). The slope of the lna vs 1/T curve just below the transition gives an activation energy of q : 4.7× 10 -2 eV for the conduction.