2001/11/30 by Kirill Shtengel, Clare C. Yu
Physics and Astronomy · #Advanced Condensed Matter Physics #Quantum and electron transport phenomena #Theoretical and Computational Physics #cond-mat.dis-nn #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.67.165106
published as Phys. Rev. B 67, 165106 (2003) · 8 pages, Latex, 6 encapsulated postscript figures, to be published in Phys. Rev. B
arxiv created 2003/03/03 · openalex publication_date 2003/04/22 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We show that 1/f noise is produced in a three-dimensional electron glass by charge fluctuations due to electron hopping between isolated sites and a percolating network at low-temperatures. The low-frequency noise spectrum goes as \ensuremathω^\ensuremath-\ensuremathα with \ensuremathα slightly larger than 1. This result together with the temperature dependence of \ensuremathα and the noise amplitude are in good agreement with the recent experiments. These results hold true both with a flat, noninteracting density of states and with a density of states that includes the Coulomb interactions. In the latter case, the density of states has a Coulomb gap that fills in with increasing temperature. For a large Coulomb gap width, this density of states gives a dc conductivity with a hopping exponent of \ensuremath≈0.75 which has been observed in recent experiments. For a small Coulomb gap width, the hopping exponent \ensuremath≈0.5.