ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
A modified Bridgman anvil high-pressure device, capable of producing hydrostatic pressures up to 8 GPa (80 kbar), was designed and built. The size of the pressure chamber (10 mm in diameter) allows the use of large specimens and simple experimental procedures. Experimental results show that hydrostatic conditions are necessary if accurate quantitative information is desired about the electrical properties of materials under pressure. Accurate data on resistance (and resistivity) versus pressure at 294 K are given for Bi, Ba, Ni, and Si. The initial pressure coefficients of R were d(ln R)dP=0.13, −7.6×10−2, −2.0×10−2, and −0.26 GPa−1, respectively. Barium has a resistance minimum near 0.9 GPa. For Bi we observe sharp transitions at 2.55, 2.7, and 7.7 GPa, and for Ba at 5.55 GPa, but we cannot verify the existence of a transition in Ba near 7 GPa. Neither do we confirm the phase transformation in Ni recently reported to occur above 2.5 GPa. For Si, R(P) agrees very well with a theoretical function calculated from the change in band gap and electron mobility with pressure.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.343360
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