Optical properties and low temperature magnetoresistance of In4(Se1−xTex)3 alloy

Highlight: • We measured optical properties and low temperature NMR of In4(Se1-xTex)3 alloy. • Dielectric responses for UV to far infrared are determined using ellipsometry. • NMR increases with doping dose, maximum NMR is -4.8% with x = 0.9. -- Abstract: Doped In4Se3 and In4Te3 have drawn much attention in their applications of thermoelectric materials. In current research, negative magnetoresistance (NMR) of In4(Se1−xTex)3 is found to be greatly enhanced with the addition of dopants when temperature lower than 100 K. NMR at 30000 Oe rises linearly with the dose of Te and Se atoms doped to In4Se3 and In4Te3, respectively. In4(Se0.1Te0.9)3 exhibits maximum NMR of −4.7% (@30000 Oe) at 10 K. Crystal structure and band gap are also determined by X-ray diffraction (XRD) and ellipsometry, respectively