Low-frequency flicker noise is usually associated with material defects or imperfection of fabrication procedure. Up to now, there is only very limited knowledge about flicker noise of the topological insulator, whose...Low-frequency flicker noise is usually associated with material defects or imperfection of fabrication procedure. Up to now, there is only very limited knowledge about flicker noise of the topological insulator, whose topologically protected conducting surface is theoretically immune to back scattering. To suppress the bulk conductivity we synthesize antimony doped Bi2Se3 nanowires and conduct transport measurements at cryogenic temperatures. The low-frequency current noise measurement shows that the noise amplitude at the high-drain current regime can be described by Hooge＇s empirical relationship, while the noise level is significantly lower than that predicted by Hooge＇s model near the Dirac point. Furthermore, different frequency responses of noise power spectrum density for specific drain currents at the low drain current regime indicate the complex origin of noise sources of topological insulator.展开更多
Two-dimensional(2D)materials have triggered enormous interest thanks to their interesting properties and potential applications,ranging from nanoelectronics to energy catalysis and biomedicals.In addition to other wid...Two-dimensional(2D)materials have triggered enormous interest thanks to their interesting properties and potential applications,ranging from nanoelectronics to energy catalysis and biomedicals.In addition to other widely investigated 2D materials,GaTe,a layered material with a direct band gap of^1.7 e V,is of importance for applications such as optoelectronics.However,detailed information on the transport properties of GaTe is yet to be explored,especially at low temperatures.Here,we report on electrical transport measurements on few-layered GaTe field effect transistors(FETs)encapsulated by h-BN at different temperatures.We find that by tuning the carrier density,ambipolar transport was realized in GaTe devices,and an electrical-field-induced metal to insulator transition(MIT)was observed when it was hole doped.The mobilities of GaTe devices show a clear dependence on temperature and increase with the decrease of temperature,reaching^1200 cm2 V-1s-1 at 3 K.Our findings may inspire further electronic studies in devices based on GaTe.展开更多
基金Supported by the National Basic Research Program of China under Grant No 2012CB921703the National Natural Science Foundation of China under Grant Nos 11174357 and 11574379the Strategic Priority Research Program of Chinese Academy of Sciences under Grant No XDB07010300
文摘Low-frequency flicker noise is usually associated with material defects or imperfection of fabrication procedure. Up to now, there is only very limited knowledge about flicker noise of the topological insulator, whose topologically protected conducting surface is theoretically immune to back scattering. To suppress the bulk conductivity we synthesize antimony doped Bi2Se3 nanowires and conduct transport measurements at cryogenic temperatures. The low-frequency current noise measurement shows that the noise amplitude at the high-drain current regime can be described by Hooge＇s empirical relationship, while the noise level is significantly lower than that predicted by Hooge＇s model near the Dirac point. Furthermore, different frequency responses of noise power spectrum density for specific drain currents at the low drain current regime indicate the complex origin of noise sources of topological insulator.
基金supported by the the National Natural Science Foundation of China(NSFC,Grant Nos.11974357,and U1932151)the State Key Research Development Program of China(Grant No.2019YFA0307800)。
文摘Two-dimensional(2D)materials have triggered enormous interest thanks to their interesting properties and potential applications,ranging from nanoelectronics to energy catalysis and biomedicals.In addition to other widely investigated 2D materials,GaTe,a layered material with a direct band gap of^1.7 e V,is of importance for applications such as optoelectronics.However,detailed information on the transport properties of GaTe is yet to be explored,especially at low temperatures.Here,we report on electrical transport measurements on few-layered GaTe field effect transistors(FETs)encapsulated by h-BN at different temperatures.We find that by tuning the carrier density,ambipolar transport was realized in GaTe devices,and an electrical-field-induced metal to insulator transition(MIT)was observed when it was hole doped.The mobilities of GaTe devices show a clear dependence on temperature and increase with the decrease of temperature,reaching^1200 cm2 V-1s-1 at 3 K.Our findings may inspire further electronic studies in devices based on GaTe.
