Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                

Suppression of low-frequency noise in two-dimensional electron gas at degenerately doped Si:P δ layers

Saquib Shamim, Suddhasatta Mahapatra, Craig Polley, Michelle Y. Simmons, and Arindam Ghosh
Phys. Rev. B 83, 233304 – Published 27 June 2011
PDFHTMLExport Citation
Abstract
Authors
Article Text
References

Abstract

We report low-frequency 1/f-noise measurements of degenerately doped Si:P δ layers at 4.2 K. The noise was found to be over six orders of magnitude lower than that of bulk Si:P systems in the metallic regime and is one of the lowest values reported for doped semiconductors. The noise was nearly independent of magnetic field at low fields, indicating negligible contribution from universal conductance fluctuations. Instead, the interaction of electrons with very few active structural two-level systems may explain the observed noise magnitude.

  • Figure
  • Figure
  • Figure
  • Figure
  • Received 6 February 2011

DOI:https://doi.org/10.1103/PhysRevB.83.233304

©2011 American Physical Society

Authors & Affiliations

Saquib Shamim1,*, Suddhasatta Mahapatra2, Craig Polley2, Michelle Y. Simmons2, and Arindam Ghosh1

  • 1Department of Physics, Indian Institute of Science, Bangalore 560 012, India
  • 2Center for Quantum Computer Technology, University of New South Wales, Sydney NSW 2052, Australia

  • *saquib@physics.iisc.ernet.in

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 83, Iss. 23 — 15 June 2011

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required

Log In
Other Options
×

Images

  • Figure 1
    Figure 1
    (a) Schematic of the device structure showing the δ layer (red/gray line) of P atoms inside Si. (b) Optical image (false color) of device S2 used in this experiment. The scale bar is 100 μm. (c) Resistivity vs temperature, T, for a device similar to the one studied in this work. (d) Magnetoconductivity plot for sample S1 at T =4.2 K. The dashed line is the weak-localization fit to the data.Reuse & Permissions
  • Figure 2
    Figure 2
    (a) The power spectral density (PSD), SV, as a function of frequency for both devices at T=4.2 K and zero magnetic field (B⊥= 0). The dashed line indicates that the spectrum is 1/f in nature. The spectrum of S2 is offset by three times for visual clarity. (b) The PSD, SV, as a function of V2 for three different channel lengths of sample S1. The solid lines shows linear fits to the data.Reuse & Permissions
  • Figure 3
    Figure 3
    (a) The normalized variance 〈δρ2〉/ρ2 as a function of area for S1 at T=4.2 K and B⊥= 0. (Inset) 〈δρ2〉/ρ2 vs B at T=4.2 K for S1. The dashed lines show average value for 〈δρ2〉/ρ2 and 1/2×〈δρ2〉/ρ2. (b) Variance 〈δρ2〉/ρ2 as a function of area for S2 at T=4.2 K and B⊥= 0. The solid lines represent 1/A variation of noise magnitude.Reuse & Permissions
  • Figure 4
    Figure 4
    Comparison of various reported values of Hooge parameter, γH, for doped silicon. Since the noise magnitude can strongly depend on temperature (T), the values of T for each reference have been explicitly stated.Reuse & Permissions
×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search

Article Lookup

Paste a citation or DOI
Enter a citation
×