论文标题
Zrb $ _ {12} $近乎bogomolnyi Point的各向异性超导性
Anisotropic superconductivity in ZrB$_{12}$ near critical Bogomolnyi point
论文作者
论文摘要
带有Ginzburg-Landau(G-L)参数($κ$)$ \ SIM1/\ SQRT {2} $的超导体存在于关键的Bogolomonyi(b)点附近,它们在类型-I和类型-II和II超级传导率之间显示出类型的型号。尽管对各向同性超导体的物理学有充分的理解,但对关键B点附近各向异性超导体物理学的实验研究仍然是一个无迹象的目标,这主要是由于模型材料系统的不可用。从理论上讲,此类超导体有望显示出I型或II型行为,以确定施加磁场的确定方向。在这里,从定向点接触的Andreev反射光谱和依赖性的AC磁敏感性测量值,我们表明Zrb $ _ {12} $是各向异性的超导体,并且它表现出依赖于场的类型I和类型II行为。这些观察结果与关键B点附近的各向异性超导体的理论期望非常吻合。因此,我们的结果项目Zrb $ _ {12} $作为模型材料系统,可以通过实验探索型各向异性超导性的物理学。
The superconductors with the Ginzburg-Landau (G-L) parameter ($κ$) $\sim1/\sqrt{2}$ exist near a critical Bogolomonyi (B) point where they show inter-type domains between type-I and type-II superconductivity. While such physics is well understood for isotropic superconductors, the experimental investigation of the physics of anisotropic superconductors near a critical B-point remains an unattained goal mainly due to the unavailability of model material systems. Theoretically, such superconductors are expected to show type-I or type-II behaviour for definite directions of an applied magnetic field. Here, from directional point-contact Andreev reflection spectroscopy and field-angle dependent ac magnetic susceptibility measurements, we show that ZrB$_{12}$ is an anisotropic superconductor, and it exhibits field-direction dependent type-I and type-II behaviour. These observations match remarkably well with the theoretical expectations for an anisotropic superconductor near a critical B-point. Therefore, our results project ZrB$_{12}$ as a model material system where the physics of inter-type anisotropic superconductivity can be explored experimentally.