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Title: Complex quantum transport in a modulation doped strained Ge quantum well heterostructure with a high mobility 2D hole gas

Abstract

The complex quantum transport of a strained Ge quantum well (QW) modulation doped heterostructure with two types of mobile carriers has been observed. The two dimensional hole gas (2DHG) in the Ge QW exhibits an exceptionally high mobility of 780 000 cm{sup 2}/Vs at temperatures below 10 K. Through analysis of Shubnikov de-Haas oscillations in the magnetoresistance of this 2DHG below 2 K, the hole effective mass is found to be 0.065 m{sub 0}. Anomalous conductance peaks are observed at higher fields which deviate from standard Shubnikov de-Haas and quantum Hall effect behaviour due to conduction via multiple carrier types. Despite this complex behaviour, analysis using a transport model with two conductive channels explains this behaviour and allows key physical parameters such as the carrier effective mass, transport, and quantum lifetimes and conductivity of the electrically active layers to be extracted. This finding is important for electronic device applications, since inclusion of highly doped interlayers which are electrically active, for enhancement of, for example, room temperature carrier mobility, does not prevent analysis of quantum transport in a QW.

Authors:
; ; ;  [1]
  1. Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)
Publication Date:
OSTI Identifier:
22594293
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 10; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CARRIER MOBILITY; DOPED MATERIALS; EFFECTIVE MASS; ELECTRONIC EQUIPMENT; HALL EFFECT; LAYERS; MAGNETORESISTANCE; QUANTUM WELLS; STRAINS; TEMPERATURE RANGE 0273-0400 K; TRANSPORT THEORY; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Morrison, C., E-mail: c.morrison.2@warwick.ac.uk, Casteleiro, C., Leadley, D. R., and Myronov, M.. Complex quantum transport in a modulation doped strained Ge quantum well heterostructure with a high mobility 2D hole gas. United States: N. p., 2016. Web. doi:10.1063/1.4962432.
Morrison, C., E-mail: c.morrison.2@warwick.ac.uk, Casteleiro, C., Leadley, D. R., & Myronov, M.. Complex quantum transport in a modulation doped strained Ge quantum well heterostructure with a high mobility 2D hole gas. United States. doi:10.1063/1.4962432.
Morrison, C., E-mail: c.morrison.2@warwick.ac.uk, Casteleiro, C., Leadley, D. R., and Myronov, M.. 2016. "Complex quantum transport in a modulation doped strained Ge quantum well heterostructure with a high mobility 2D hole gas". United States. doi:10.1063/1.4962432.
@article{osti_22594293,
title = {Complex quantum transport in a modulation doped strained Ge quantum well heterostructure with a high mobility 2D hole gas},
author = {Morrison, C., E-mail: c.morrison.2@warwick.ac.uk and Casteleiro, C. and Leadley, D. R. and Myronov, M.},
abstractNote = {The complex quantum transport of a strained Ge quantum well (QW) modulation doped heterostructure with two types of mobile carriers has been observed. The two dimensional hole gas (2DHG) in the Ge QW exhibits an exceptionally high mobility of 780 000 cm{sup 2}/Vs at temperatures below 10 K. Through analysis of Shubnikov de-Haas oscillations in the magnetoresistance of this 2DHG below 2 K, the hole effective mass is found to be 0.065 m{sub 0}. Anomalous conductance peaks are observed at higher fields which deviate from standard Shubnikov de-Haas and quantum Hall effect behaviour due to conduction via multiple carrier types. Despite this complex behaviour, analysis using a transport model with two conductive channels explains this behaviour and allows key physical parameters such as the carrier effective mass, transport, and quantum lifetimes and conductivity of the electrically active layers to be extracted. This finding is important for electronic device applications, since inclusion of highly doped interlayers which are electrically active, for enhancement of, for example, room temperature carrier mobility, does not prevent analysis of quantum transport in a QW.},
doi = {10.1063/1.4962432},
journal = {Applied Physics Letters},
number = 10,
volume = 109,
place = {United States},
year = 2016,
month = 9
}
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