TY - JOUR

T1 - Electron mass in a HgTe quantum well: Experiment versus theory

AU - Minkov, G. M.

AU - Aleshkin, V. Ya

AU - Rut, O. E.

AU - Sherstobitov, A. A.

AU - Germanenko, A. V.

AU - Dvoretski, S. A.

AU - Mikhailov, N. N.

N1 - Funding Information: We are grateful to I.V. Gornyi for useful discussions. The work has been supported in part by the Russian Foundation for Basic Research (Grant No. 18-02-00050 ), by Act 211 Government of the Russian Federation , agreement No. 02.A03.21.0006 , by the Ministry of Education and Science of the Russian Federation under Project No. 3.9534.2017/8.9 , and by the FASO of Russia (theme “Electron” No. 01201463326 ). Publisher Copyright: © 2019 Elsevier B.V. Copyright: Copyright 2019 Elsevier B.V., All rights reserved.

PY - 2020/2

Y1 - 2020/2

N2 - The energy spectrum of the conduction band in HgTe/CdxHg1−xTe quantum wells with a width d=(4.6−20.2)nm has been experimentally studied in a wide range of electron density. For this purpose, the electron density dependence of the effective mass was measured by two methods: by analyzing the temperature dependence of the Shubnikov–de Haas oscillations and by means of the quantum capacitance measurements. There was shown that the effective mass obtained for the structures with dc, where dc≃6.3nm is a critical width of quantum well corresponding to the Dirac-like energy spectrum, is close to the calculated values over the whole electron density range; with increasing width, at d>(7−8)nm, the experimental effective mass becomes noticeably less than the calculated ones. This difference increases with the electron density decrease, i.e., with lowering the Fermi energy; the maximal difference between the theory and experiment is achieved at d=(15−18)nm, where the ratio between the calculated and experimental masses reaches the value of two and begins to decrease with a further d increase. We assume that observed behavior of the electron effective mass results from the spectrum renormalization due to many-body effects.

AB - The energy spectrum of the conduction band in HgTe/CdxHg1−xTe quantum wells with a width d=(4.6−20.2)nm has been experimentally studied in a wide range of electron density. For this purpose, the electron density dependence of the effective mass was measured by two methods: by analyzing the temperature dependence of the Shubnikov–de Haas oscillations and by means of the quantum capacitance measurements. There was shown that the effective mass obtained for the structures with dc, where dc≃6.3nm is a critical width of quantum well corresponding to the Dirac-like energy spectrum, is close to the calculated values over the whole electron density range; with increasing width, at d>(7−8)nm, the experimental effective mass becomes noticeably less than the calculated ones. This difference increases with the electron density decrease, i.e., with lowering the Fermi energy; the maximal difference between the theory and experiment is achieved at d=(15−18)nm, where the ratio between the calculated and experimental masses reaches the value of two and begins to decrease with a further d increase. We assume that observed behavior of the electron effective mass results from the spectrum renormalization due to many-body effects.

KW - Electron transport

KW - Energy spectrum

KW - Quantum wells

KW - TEMPERATURE-DEPENDENCE

KW - BAND-STRUCTURE

UR - http://www.scopus.com/inward/record.url?scp=85073527765&partnerID=8YFLogxK

U2 - 10.1016/j.physe.2019.113742

DO - 10.1016/j.physe.2019.113742

M3 - Article

AN - SCOPUS:85073527765

VL - 116

JO - Physica E: Low-Dimensional Systems and Nanostructures

JF - Physica E: Low-Dimensional Systems and Nanostructures

SN - 1386-9477

M1 - 113742

ER -