Excess Noise in Semiconductors

Item

Title
Excess Noise in Semiconductors
Creator
Brophy, James J.
Date
1962
Identifier
AD0288874
AD0288874
Abstract
Critical point polarization fluctuations in ferroelectric triglycene sulfate crystals were measured at the curie temperature by observing noise voltages between electrodes applied to the crystal. In barium titanate crystals a thermal Barkhausen noise with a 1/f power spectrum is observed when the crystal temperature is passed slowly through the curie point. Experimentally it was found that the noise voltage appearing across a metallic conductor heated to high temperatures by dc current flow is given by the Nyquist theorem, even though the conductor is not in thermodynamic equilibrium. In semiconductors fluctuations in optical absorption at wavelengths beyond the fundamental absorption edge caused by free carrier scattering are expected. A simple experiment employing an infrared interferometer was capable of detecting such fluctuations in optical absorption
Date Issued
1962-11-14
Extent
1
Corporate Author
Armour Research Foundation
AD Number
AD-288 874
Contract
Nonr-180000
DoD Project
NR 017-432
Distribution Conflict
No
Index In
U.S. Government Research Reports, Vol. 38, No. 4, p. 40
Index Price
$6.60
Distribution Classification
1
DTIC Record Exists
Yes
Report Availability
Not available via Contrails
Type
report