标题： 场角分辨比热振荡的符号反转在重费米子超导体CeCoIn$_5$和$d_{x^2-y^2}$的配对对称性中 显示英文标题

标题： Sign reversal of field-angle resolved heat capacity oscillations in a heavy fermion superconductor CeCoIn$_5$ and $d_{x^2-y^2}$ pairing symmetry

摘要： 为了确定CeCoIn5 (Tc=2.3 K)中的超导能隙对称性，我们在磁场绕c轴旋转的情况下进行了角度分辨比热（C_\phi ）测量，温度低至0.05Tc，并进行了详细的理论计算。 在1 T的磁场下，当进入经典近似区域时，在T ~ 0.1Tc处观察到了C_\phi 中四重角振荡的符号反转，此时C_\phi 的最大值对应于反节点方向，与角度分辨态密度（ADOS）计算一致。 C_\phi 的行为显示出沿[110]方向的极小值，明确地使我们得出该系统的d_{x平方减y平方} 对称性。 ADOS-经典近似区域局限于T/Tc ~ 0.1和1.5 T（0.13Hc2）的狭窄温度和磁场范围内。 显示英文摘要

摘要： To identify the superconducting gap symmetry in CeCoIn5 (Tc=2.3 K), we performed angle-resolved specific heat (C_\phi) measurements in a field rotated around the c-axis down to very low temperatures 0.05Tc and detailed theoretical calculations. In a field of 1 T, a sign reversal of the fourfold angular oscillation in C_\phi has been observed at T ~ 0.1Tc on entering a quasiclassical regime where the maximum of C_\phi corresponds to the antinodal direction, coinciding with the angle-resolved density of states (ADOS) calculation. The C_\phi behavior, which exhibits minima along [110] directions, unambiguously allows us to conclude d_{x^2-y^2} symmetry of this system. The ADOS-quasiclassical region is confined to a narrow T and H domain within T/Tc ~ 0.1 and 1.5 T (0.13Hc2).