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Title: Shot noise in systems with semi-Dirac points

Abstract

We calculate the ballistic conductance and shot noise of electrons through a two-dimensional stripe system (width W ≫ length L) with semi-Dirac band-touching points. We find that the ratio between zero-temperature noise power and mean current (the Fano factor) is highly anisotropic. When the transport is along the linear-dispersion direction and the Fermi energy is fixed at the semi-Dirac point, the Fano factor has a universal value F = 0.179 while a minimum conductivity exists and scales with L{sup 1∕2}. Along the parabolic dispersion direction, the Fano factor at the semi-Dirac point has a contact-independent limit exceeding 0.9, which varies weakly with L due to the common-path interference of evanescent waves. Our findings suggest a way to discern the type of band-touching points.

Authors:
;  [1]
  1. Center of Statistical and Theoretical Condensed Matter Physics and Department of Physics, Zhejiang Normal University, Jinhua 321004 (China)
Publication Date:
OSTI Identifier:
22314600
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 6; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CURRENTS; DISPERSION RELATIONS; ELECTRONS; FANO FACTOR; INTERFERENCE; LENGTH; QUANTUM STATES; TEMPERATURE NOISE; TEMPERATURE ZERO K

Citation Formats

Zhai, Feng, and Wang, Juan. Shot noise in systems with semi-Dirac points. United States: N. p., 2014. Web. doi:10.1063/1.4892843.
Zhai, Feng, & Wang, Juan. Shot noise in systems with semi-Dirac points. United States. doi:10.1063/1.4892843.
Zhai, Feng, and Wang, Juan. Thu . "Shot noise in systems with semi-Dirac points". United States. doi:10.1063/1.4892843.
@article{osti_22314600,
title = {Shot noise in systems with semi-Dirac points},
author = {Zhai, Feng and Wang, Juan},
abstractNote = {We calculate the ballistic conductance and shot noise of electrons through a two-dimensional stripe system (width W ≫ length L) with semi-Dirac band-touching points. We find that the ratio between zero-temperature noise power and mean current (the Fano factor) is highly anisotropic. When the transport is along the linear-dispersion direction and the Fermi energy is fixed at the semi-Dirac point, the Fano factor has a universal value F = 0.179 while a minimum conductivity exists and scales with L{sup 1∕2}. Along the parabolic dispersion direction, the Fano factor at the semi-Dirac point has a contact-independent limit exceeding 0.9, which varies weakly with L due to the common-path interference of evanescent waves. Our findings suggest a way to discern the type of band-touching points.},
doi = {10.1063/1.4892843},
journal = {Journal of Applied Physics},
number = 6,
volume = 116,
place = {United States},
year = {Thu Aug 14 00:00:00 EDT 2014},
month = {Thu Aug 14 00:00:00 EDT 2014}
}
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