Unusual evolution of B_{c2} and T_c with inclined fields in restacked TaS_2 nanosheets

Yonghui Ma; Jie Pan; Chenguang Guo; Xuan Zhang; Lingling Wang; Tao Hu; Gang Mu; Fuqiang Huang; Xiaoming Xie

doi:10.1038/s41535-018-0107-2

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arXiv · 1712.07763

Unusual evolution of B_{c2} and T_c with inclined fields in restacked TaS_2 nanosheets

Yonghui Ma·Jie Pan·Chenguang Guo·Xuan Zhang·Lingling Wang·Tao Hu·Gang Mu·Fuqiang Huang·Xiaoming Xie

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Abstract

Recently we reported an enhanced superconductivity in restacked monolayer TaS_2 nanosheets compared with the bulk TaS_2, pointing to the exotic physical properties of low dimensional systems. Here we tune the superconducting properties of this system with magnetic field along different directions, where a strong Pauli paramagnetic spin-splitting effect is found in this system. Importantly, an unusual enhancement as high as 3.8 times of the upper critical field B_{c2}, as compered with the Ginzburg-Landau (GL) model and Tinkham model, is observed under the inclined external magnetic field. Moreover, with the out-of-plane field fixed, we find that the superconducting transition temperature T_c can be enhanced by increasing the in-plane field and forms a dome-shaped phase diagram. An extended GL model considering the special microstructure with wrinkles was proposed to describe the results. The restacked crystal structure without inversion center along with the strong spin-orbit coupling may also play an important role for our observations.

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Yonghui Ma, Jie Pan, Chenguang Guo, Xuan Zhang, Lingling Wang, Tao Hu, Gang Mu, Fuqiang Huang, Xiaoming Xie. 2017-12-21. Unusual evolution of B_{c2} and T_c with inclined fields in restacked TaS_2 nanosheets. https://doi.org/10.1038/s41535-018-0107-2

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