Kar, Swastik and Raychaudhuri, AK and Ghosh, Arindam and Löhneysen, HV and Weiss, G (2003) Observation of Non-Gaussian Conductance Fluctuations at Low Temperatures in Si:P(B) at the Metal-Insulator Transition. In: Physical Review Letters, 91 (21). 216603/1-4.
We report investigations of conductance fluctuations (with 1/f alpha power spectra) in doped silicon at low temperatures (T<20 K) as it is tuned through the metal-insulator transition (MIT) by changing the carrier concentration n. The scaled magnitude of noise, gamma H, increases with decreasing T following an approximate power law gamma H/~T- beta. At low T, gamma H diverges as n decreases through the critical concentration n/c, accompanied by a growth of low-frequency spectral weight. The second spectrum and probability density of the fluctuations show strong non-Gaussian behavior below 20 K as n/nc decreases through 1. This is interpreted as the onset of a glassy freezing of the electronic system across the MIT.
|Item Type:||Journal Article|
|Additional Information:||Copyright for this article belongs to American Physical Society (APS).|
|Department/Centre:||Division of Physical & Mathematical Sciences > Physics|
|Date Deposited:||04 Nov 2004|
|Last Modified:||19 Sep 2010 04:17|
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