Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, 70803, USA.
Department of Physics, National Cheng Kung University, Tainan, 701, Taiwan.
Sci Rep. 2023 Apr 26;13(1):6824. doi: 10.1038/s41598-023-33237-5.
PdTe is a superconductor with T ~ 4.25 K. Recently, evidence for bulk-nodal and surface-nodeless gap features has been reported in PdTe. Here, we investigate the physical properties of PdTe in both the normal and superconducting states via specific heat and magnetic torque measurements and first-principles calculations. Below T, the electronic specific heat initially decreases in T behavior (1.5 K < T < T) then exponentially decays. Using the two-band model, the superconducting specific heat can be well described with two energy gaps: one is 0.372 meV and another 1.93 meV. The calculated bulk band structure consists of two electron bands (α and β) and two hole bands (γ and η) at the Fermi level. Experimental detection of the de Haas-van Alphen (dHvA) oscillations allows us to identify four frequencies (F = 65 T, F = 658 T, F = 1154 T, and F = 1867 T for H // a), consistent with theoretical predictions. Nontrivial α and β bands are further identified via both calculations and the angle dependence of the dHvA oscillations. Our results suggest that PdTe is a candidate for unconventional superconductivity.
碲化钯是一种超导材料，超导转变温度约为 4.25K。最近，在碲化钯中报道了体节点和表面无节点能隙特征的证据。在这里，我们通过比热和磁转矩测量以及第一性原理计算来研究 PdTe 在正常态和超导态下的物理性质。在 T 以下，电子比热最初呈 T 行为（1.5 K < T < T）下降，然后指数衰减。使用双带模型，可以很好地用两个能隙来描述超导比热：一个是 0.372 meV，另一个是 1.93 meV。计算得到的体能带结构在费米能级处包含两个电子带（α和β）和两个空带（γ和η）。对德哈斯-范阿尔芬（dHvA）振荡的实验检测使我们能够识别出四个频率（H // a 时为 F = 65 T、F = 658 T、F = 1154 T 和 F = 1867 T），这与理论预测一致。通过计算和 dHvA 振荡的角度依赖性，进一步确定了非平凡的α和β带。我们的结果表明，碲化钯是非常规超导的候选材料。
