Thermoelectric properties of Bi2Sr2Co2O9 whiskers under hydrostatic pressure
نویسندگان
چکیده
We report the temperature dependence of thermopower (S) in the ab plane of Bi2Sr2Co2O9 ~BC-222! single crystalline whiskers under high pressure up to 1.2 GPa. Special modifications were made to our high-pressure transport measurement system to improve the measurement accuracy of S for whiskers with high resistance. Pressure improved the contact resistance dramatically. We observed a slight decrease of S and four-wire electrical conductivity ~s! under high pressure. As a result, the power factor (Ss) was decreased less than 20% by pressure. From the temperature dependence of s, the band gap of BC-222 whiskers increase very slightly under high pressure. © 2002 American Institute of Physics. @DOI: 10.1063/1.1510160#
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