Temperature and Electron Concentration Dependences of 1/f Noise in Hg$_{1-x}$Cd$_x$Te -- Evidence for a Mobility Fluctuations Mechanism

Adil Rehman; Volodymyr Petriakov; Ivan Yahniuk; Aleksandr Kazakov; Iwona Rogalska; Jakub Grendysa; Michał Marchewka; Maciej Haras; Tomasz Wojtowicz; Grzegorz Cywiński; Wojciech Knap; Sergey Rumyantsev

arXiv · 2410.23755

Temperature and Electron Concentration Dependences of 1/f Noise in Hg$_{1-x}$Cd$_x$Te -- Evidence for a Mobility Fluctuations Mechanism

Adil Rehman·Volodymyr Petriakov·Ivan Yahniuk·Aleksandr Kazakov·Iwona Rogalska·Jakub Grendysa·Michał Marchewka·Maciej Haras·Tomasz Wojtowicz·Grzegorz Cywiński·Wojciech Knap·Sergey Rumyantsev

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Abstract

Hg$_{1-x}$Cd$_x$Te is a unique material with the band-gap tunable by the temperature, pressure, and cadmium content in a wide range, from 1.6 eV to inverted band-gap of -0.3 eV. This makes Hg$_{1-x}$Cd$_x$Te one of the key materials for infrared and terahertz detectors, whose characteristics largely depend on the material noise properties. In this work, we investigated the low-frequency 1/f noise in a thick (800 nm) HgCdTe layer and in a field effect transistor (FET) with an 8 nm wide HgTe quantum well. Both structures exhibited a small contribution from contact noise and showed weak noise dependences on temperature. Investigation of the 1/f noise in HgTe quantum well FET as a function of gate voltage revealed that the noise also depends weakly on electron concentration. These findings indicate that the noise properties of Hg$_{1-x}$Cd$_x$Te are similar to those of graphene, where mobility fluctuations were found to be the dominant mechanism of the 1/f noise.

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Adil Rehman, Volodymyr Petriakov, Ivan Yahniuk, Aleksandr Kazakov, Iwona Rogalska, Jakub Grendysa, Michał Marchewka, Maciej Haras, Tomasz Wojtowicz, Grzegorz Cywiński, Wojciech Knap, Sergey Rumyantsev. 2024-10-31. Temperature and Electron Concentration Dependences of 1/f Noise in Hg$_{1-x}$Cd$_x$Te -- Evidence for a Mobility Fluctuations Mechanism. https://arxiv.org/abs/2410.23755

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