Magneto-transport Spectroscopy of the First and Second Two-dimensional Subbands in Al0.25Ga0.75N/GaN Quantum Point Contacts

Magnetic transport spectroscopy is investigated in quantum point contacts (QPCs) fabricated in Al 0.25 Ga 0.75 N/GaN heterostructures. The magnetic field perpendicular to the two-dimensional electron gas (2DEG) is shown to depopulate the quasi-one-dimensional energy levels in the first two-dimension...

Full description

Saved in:
Bibliographic Details
Published in:Scientific reports 2017-02, Vol.7 (1), p.42974-42974, Article 42974
Main Authors: Lu, Fangchao, Tang, Ning, Shang, Liangliang, Guan, Hongming, Xu, Fujun, Ge, Weikun, Shen, Bo
Format: Article
Language:English
Subjects:
142/126
639/766/1130/2798
639/766/119/1000
Energy
Humanities and Social Sciences
Magnetic fields
multidisciplinary
Science
Spectroscopy
Spectrum analysis
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Magnetic transport spectroscopy is investigated in quantum point contacts (QPCs) fabricated in Al 0.25 Ga 0.75 N/GaN heterostructures. The magnetic field perpendicular to the two-dimensional electron gas (2DEG) is shown to depopulate the quasi-one-dimensional energy levels in the first two-dimensional (2D) subband faster than those in the second one. In GaN based heterostructures, the energy levels in the second 2D subband is generally concealed in the fast course of depletion and hence rarely detected. The perpendicular magnetic field facilitates the observation of the second 2D subband, and provides a method to study the properties of these energy levels. A careful analysis on the rate of the magnetic depletion with respect to the level index and confinement is carried out, from which the profile of the lateral confinement in GaN based QPCs is found to be triangular. The stability diagram at T shows the energy separation between the first and second 2D subband to be in the range of 32 to 42 meV.
ISSN:2045-2322
2045-2322
DOI:10.1038/srep42974