Anisotropy of a cubic synthetic mineral superconductor Rh₁₇S₁₅ in a magnetic field

Miassite Rh₁₇S₁₅ is a rare mineral superconductor with T_c=5.4K [1] and very high upper critical fields, H_c2(0), above 20 T [2], well in excess of the paramagnetic Pauli limit. Recently we showed that the superconducting state of miassite is unconventional, with line nodes in the superconducting gap [3]. To get an additional insight into this exotic superconducting material we studied the anisotropy of the upper critical field using magnetization and electrical resistivity measurements. Single crystals, with the residual resistivity ratio of 10, were synthesized by self-flux technique. Surprisingly, for a cubic material, a notable anisotropy of the upper critical field between the [100], [110] and [111] orientations of magnetic field is found. A significant anisotropy is also obtained in the magnetic and transport response in the high-field superconducting vortex state.

[1] B.T.Matthias, E. Corenzwit, and C.E.Miller, Phys. Rev. 93, 1415 (1954).

[2] M. Uhlarz, O. Ignatchik, J. Wosnitza, H. R. Naren, A. Thamizhave, and S. Ramakrishnan, J. Low Temp. Phys. 159, 176 (2010).

[3] Hyunsoo Kim, Makariy A. Tanatar, Marcin Kończykowski, Udhara S. Kaluarachchi, Serafim Teknowijoyo, Kyuil Cho, Aashish Sapkota, John M. Wilde, Matthew J. Krogstad, Sergey L. Bud'ko, Philip M. R. Brydon, Paul C. Canfield, Ruslan Prozorov, arXiv:2306.00261.