HfTe₃ single crystal undergoes a charge-density-wave (CDW) transition at T_CDW = 93 K without the appearance of superconductivity (SC) down to 50 mK at ambient pressure. Here, we determined its CDW vector q = 0.91(1) a* + 0.27(1) c* via low-temperature transmission electron microscope and then performed comprehensive high-pressure transport measurements along three major crystallographic axes. Our results indicate that the superconducting pairing starts to occur within the quasi-one-dimensional (Q1D) -Te2-Te3- chain at 4–5 K but the phase coherence between the superconducting chains cannot be realized along either the b- or c-axis down to at least 1.4 K, giving rise to an extremely anisotropic SC rarely seen in real materials. We have discussed the prominent Q1D SC in pressurized HfTe₃ in terms of the anisotropic Fermi surfaces arising from the unidirectional Te-5p_x electronic states and the local pairs formed along the -Te2-Te3- chains based on the first-principles electronic structure calculations.

HfTe ₃单晶在T _CDW  = 93 K 时经历电荷密度波 (CDW) 跃迁，而在环境压力下低至 50 mK 时不会出现超导性 (SC)。在这里，我们通过低温透射电子显微镜确定了其 CDW 矢量q  = 0.91(1) a * + 0.27(1) c *，然后沿三个主要晶轴进行了全面的高压输运测量。我们的结果表明超导配对开始发生在准一维 (Q1D) -Te2-Te3- 链中，温度为 4-5 K，但超导链之间的相位相干无法沿b-或c- 实现轴下降到至少 1.4 K，从而产生在真实材料中很少见的极其各向异性的 SC。我们已经讨论了加压 HfTe ₃中突出的 Q1D SC，这涉及基于第一性原理电子结构计算的单向 Te-5p _x电子态和沿 -Te2-Te3- 链形成的局部对产生的各向异性费米表面.