Cedomir Petrovic, Brookhaven National Lab

The connection between superconducting and competing order with crystalline disorder is of interest in many superconducting materials. Superconductivity and charge-density-wave (CDW) are traditionally viewed as Fermi surface instabilities due to electron-phonon coupling whereas arguments have been made both for their cooperation and competition [1-3]. In copper oxides or Fe-based superconductors dome of high superconducting Tc exists at a rather complex phase diagram where disorder and various forms of symmetry breaking orders are present, such as spindensity, CDW or nematic order [4-5]. In this talk I will discuss connection between superconductivity and disorder in several chalcogenide superconductors. These include ZrTe3 and 2H-TaSe2-xSx CDW materials where superconducting domes exist in the absence of magnetism [6-10] and FeSe1-xSx (0 <= x <=1) crystals where nematic order coexists with superconductivity for some range of x.

References:

[1] G. Gruner, Rev. Mod. Phys. 60, 1129 (1988),
[2] T. Kiss et al., Nature Physics 3,720 (2007),
[3] S. V. Borisenko et al., Phys. Rev. Lett. 102, 166402 (2009).
[4] E. Fradkin et al.,Rev. Mod. Phys. 87, 457 (2015),
[5] R. M. Fernandes et al., Nature Physics 10, 97 (2014)
[6] Xiangde Zhu et al., Phys. Rev. Lett. 106, 246404 (2011),
[7] Hechang Lei et al., Europhys. Lett.95, 17001 (2011),
[8] Xiangde Zhu et al., Sci. Rep. 6, 26974 (2016),
[9] Lijun Li et al., NPJ Quantum Materials 2, 11 (2017).
[10] Phys. Rev. Lett. 122, 017601 (2019).