THERMODYNAMIC EVIDENCE FOR A LOW-TEMPERATURE PHASE-TRANSITION IN THE ORGANIC CONDUCTOR ALPHA-(BEDT-TTF)(2)MHG(SCN)(4)(FOR M=K,RB)

被引:16
作者
HENNING, PF
BROOKS, JS
CROW, JE
TANAKA, Y
KINOSHITA, T
KINOSHITA, N
TOKUMOTO, M
ANZAI, H
机构
[1] FLORIDA STATE UNIV,NATL HIGH MAGNET FIELD LAB,TALLAHASSEE,FL 32306
[2] BOSTON UNIV,DEPT PHYS,BOSTON,MA 02215
[3] ELECTROTECH LAB,TSUKUBA,IBARAKI 305,JAPAN
[4] HIMEJI INST TECHNOL,HIMEJI,HYOGO 67122,JAPAN
关键词
ORGANIC CONDUCTORS; AC SPECIFIC HEAT; DENSITY WAVE TRANSITION;
D O I
10.1016/0038-1098(95)00340-1
中图分类号
O469 [凝聚态物理学];
学科分类号
070205 ;
摘要
We have measured the ac heat capacity of the organic conductor alpha-(BEDT-TTF)(2)MHg(SCN)(4) (for M = K, Rb) via a low addenda optically heated calorimetric method. We find, contrary to previous reports, a rise Delta C in the heat capacity near a transition temperature T-DW. The BCS parameter Delta C/gamma T-c for the transitions ranges from 7.5 to 0.1 depending on different estimates of the electronic density of states. Nevertheless, the results are consistent with the opening of a density wave gap at T-DW in the open orbit band, and a reconstruction of the closed orbit band at lower temperatures.
引用
收藏
页码:691 / 694
页数:4
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