Low-temperature thermal expansion of amorphous solids

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1982

DOI:https://doi.org/10.2172/6737431· OSTI ID:6737431

Ackerman, David Alan ^[1]

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1. Univ. of Illinois, Urbana-Champaign, IL (United States)

For most amorphous materials at temperatures below approx. = 1 K, the magnitudes and temperature dependences of specific heat, thermal conductivity and ultrasonic dispersion are qualitatively similar, independent of chemical composition. It has been suggested that thermal expansion also exhibits this universal behavior. The development of a dilatometer capable of resolving sample strains as small as 10^-12 has permitted measurement of the linear thermal expansion of various glasses below 1 K. These investigations have demonstrated, however, that the low-temperature thermal expansion coefficient of glasses can be positive, negative, large or small. Analysis of measurements performed on two types of vitreous silica, two amorphous polymers, As₂S₃ and ZrO₂:Y₂O₃ is presented in the context of the phenomenological tunneling-states model. Consistency in explanation of thermal expansion and ultrasonic behavior is maintained by assuming a broad, weakly energy-dependent distribution of coupling strengths between phonons and the localized excitations thought to be characteristic of the glassy state.

• Research Organization: Univ. of Illinois, Urbana-Champaign, IL (United States)
• Sponsoring Organization: USDOE Office of Energy Research (ER)
• DOE Contract Number: AC02-76ER01198
• OSTI ID: 6737431
• Report Number(s): DOE/ER/01198--1390; ON: DE83001128
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
AMORPHOUS STATE
ARSENIC COMPOUNDS
ARSENIC SULFIDES
CHALCOGENIDES
DIELECTRIC MATERIALS
DILATOMETRY
ELECTRONIC EQUIPMENT
EQUIPMENT
EXPANSION
EXTENSOMETERS
FLUXMETERS
GLASS
MATERIALS
MEASURING INSTRUMENTS
MICROWAVE EQUIPMENT
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
SILICA
SILICON COMPOUNDS
SILICON OXIDES
SQUID DEVICES
SULFIDES
SULFUR COMPOUNDS
SUPERCONDUCTING DEVICES
THERMAL ANALYSIS
THERMAL EXPANSION
TRANSITION ELEMENT COMPOUNDS
ULTRALOW TEMPERATURE
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES