Most parent compounds of iron-based superconductors (FeSCs) exhibit a tetragonal-to-orthorhombic lattice distortion below T_s associated with an electronic nematic phase that breaks the four-fold (C₄) rotational symmetry of the underlying lattice, and then forms collinear antiferromagnetic (AF) order below T_N (T_N ≤ T_s). Optimal superconductivity emerges upon suppression of the nematic and AF phases. FeSe, which also exhibits a nematic phase transition below T_s but becomes superconducting in the nematic phase without AF order, provides a unique platform to study the interplay amongst the nematic phase and superconductivity. In this review, we focus on the experiments done on uniaxial pressure detwinned single crystals of FeSe compared to other FeSCs and highlight the importance of understanding the electronic and magnetic anisotropy in elucidating the nature of unconventional superconductivity.

铁基超导体（FeSCs）的大多数母体化合物在以下温度下表现出四方晶向正交晶格畸变 Ť_s 与电子向列相相关，该相将打破四倍（C₄）下面的晶格旋转对称，然后在下面形成共线反铁磁（AF）阶Ť_ñ （Ť_ñ ≤ Ť_s）。抑制向列相和AF相后，就会出现最佳的超导性。FeSe，在下面还表现出向列相变Ť_s但在没有AF阶的向列相中变为超导，提供了一个独特的平台来研究向列相与超导之间的相互作用。在这篇综述中，我们将重点放在与其他FeSC相比对FeSe的单轴压力解缠单晶上进行的实验上，并强调理解电子和磁各向异性在阐明非常规超导性质方面的重要性。