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