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Title: Alternating current calorimeter for specific heat capacity measurements at temperatures below 10 K and pressures up to 10 GPa

Abstract

A developed alternating current calorimeter for measuring the absolute value of specific heat C of a very small sample under a pressure up to 10 GPa and low temperature below 10 K is described. A Bridgman anvil cell made of tungsten carbide with a top diameter of 3 mm is used. A hollow at the top prevents expansion of the sample space over the anvil top. Two chip resistors, which act as a thermometer and a heater, are mounted on the outer part of a copper–beryllium gasket with a frying pan-like shape. Thus, the thermometer is not pressurized. In order to isolate the gasket from the anvil thermally, diamond powder with a grain size of 0.25 μm is placed on the anvil top. Two jumps of C at the superconducting transitions of Pb (3.3 mg) and In (5.0 mg) are observed under various pressures up to 9 GPa, as clearly as those at the ambient pressure.

Authors:
 [1]
  1. Cryogenics and Instrumental Analysis Division, N-BARD, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8526 (Japan)
Publication Date:
OSTI Identifier:
22597979
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 87; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALTERNATING CURRENT; BERYLLIUM; CALORIMETERS; COPPER; DIAMONDS; EXPANSION; GASKETS; GRAIN SIZE; HEATERS; POWDERS; PRESSURE RANGE GIGA PA; RESISTORS; SPECIFIC HEAT; TEMPERATURE RANGE 0000-0013 K; THERMOMETERS; TUNGSTEN CARBIDES

Citation Formats

Umeo, Kazunori, E-mail: kumeo@sci.hiroshima-u.ac. Alternating current calorimeter for specific heat capacity measurements at temperatures below 10 K and pressures up to 10 GPa. United States: N. p., 2016. Web. doi:10.1063/1.4952959.
Umeo, Kazunori, E-mail: kumeo@sci.hiroshima-u.ac. Alternating current calorimeter for specific heat capacity measurements at temperatures below 10 K and pressures up to 10 GPa. United States. doi:10.1063/1.4952959.
Umeo, Kazunori, E-mail: kumeo@sci.hiroshima-u.ac. 2016. "Alternating current calorimeter for specific heat capacity measurements at temperatures below 10 K and pressures up to 10 GPa". United States. doi:10.1063/1.4952959.
@article{osti_22597979,
title = {Alternating current calorimeter for specific heat capacity measurements at temperatures below 10 K and pressures up to 10 GPa},
author = {Umeo, Kazunori, E-mail: kumeo@sci.hiroshima-u.ac},
abstractNote = {A developed alternating current calorimeter for measuring the absolute value of specific heat C of a very small sample under a pressure up to 10 GPa and low temperature below 10 K is described. A Bridgman anvil cell made of tungsten carbide with a top diameter of 3 mm is used. A hollow at the top prevents expansion of the sample space over the anvil top. Two chip resistors, which act as a thermometer and a heater, are mounted on the outer part of a copper–beryllium gasket with a frying pan-like shape. Thus, the thermometer is not pressurized. In order to isolate the gasket from the anvil thermally, diamond powder with a grain size of 0.25 μm is placed on the anvil top. Two jumps of C at the superconducting transitions of Pb (3.3 mg) and In (5.0 mg) are observed under various pressures up to 9 GPa, as clearly as those at the ambient pressure.},
doi = {10.1063/1.4952959},
journal = {Review of Scientific Instruments},
number = 6,
volume = 87,
place = {United States},
year = 2016,
month = 6
}
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