三元超导化合物Sc_5Ir_4Si_(10)的低温比热性质  

Characteristics of Low Temperature Specific Heat in Superconducting Sc_5Ir_4Si_(10) Single Crystal

作　　者：顾冬梅[1,2] 王智河[1] 于广亮[1] 邱里[1] 施智祥[2] 

机构地区：[1]南京大学物理系,江苏南京210093 [2]东南大学物理系,江苏南京210096

出　　处：《稀有金属材料与工程》2008年第A04期49-52,共4页Rare Metal Materials and Engineering

摘　　要：在零场下2～300K以及不同磁场下2～10K温度范围内,分别测量了超导Sc5Ir4Si10单晶的比热。采用4-Einstein峰拟合声子谱的方法对高温部分进行处理,成功地分离了Sc5Ir4Si10的晶格比热和电子比热。10K以下的比热遵守经典的超导理论,即晶格比热与温度的三次方成正比,电子比热符合温度的幂指数关系。4K以下电子比热的磁场关系为ΔCe/T∝Hα,其中α与温度有关。随着温度的降低α的值从0.67增大到0.76,表明Sc5Ir4Si10的超导配对可能是s波和d波混合波,并由d波向s波转化。Specific heat of superconducting Sc5Ir4Si10 single crystal has been measured by relaxation technique from 2 K to 300 K at 0 T and from 2 K to 10K in various fields, respectively. The electronic and lattice specific heats were separated successfully by fitting the phonon spectrum in high temperature region using the 4 Einstein peaks. It is found that the specific heat below 10 K follows the classical Bardeen-Cooper-Schreiffer （BCS） theory, namely, the lattice contribution is proportional to the cube of temperature. And the temperature dependence of electric specific heat follows an exponential law. The magnetic dependence of electric specific heat below 4K is ΔC/T∝Hα, where α depends on the temperature. As the temperature decreases, α increases from 0.67 to 0.76, indicating that the superconducting pairing for Sc5Ir4Si10 might be a mixed wave of s-wave and d-wave. It also transforms from d-wave to s-wave as the temperature decreases.

关 键 词：Sc5Ir4Si10单晶 比热 超导电子配对机制 

分 类 号：O511.4[理学—低温物理]