2016/02/29 by Shingo Yonezawa, Kengo Tajiri, S. Nakata +7 · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Critical field #Liquid crystal #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Superconductivity #Symmetry (geometry) #Symmetry breaking #Topological Materials and Phenomena #cond-mat.mtrl-sci #cond-mat.soft #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1038/nphys3907
published as Nature Phys. 17, 123-126 (2017). (published online: 10 Oct 2016) · 12 pages, 3 figures; plus 18 pages of Supplementary Materials (incl. 10 figures)
openalex publication_date 2016/10/10 · arxiv created 2016/10/11 · arxiv updated 2017/03/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Unconventional superconductivity is characterized by the spontaneous symmetry breaking of the macroscopic superconducting wavefunction in addition to the gauge symmetry breaking, such as rotational-symmetry breaking with respect to the underlying crystal-lattice symmetry. Particularly, superconductivity with spontaneous rotational-symmetry breaking in the wavefunction amplitude and thus in bulk properties, not yet reported previously, is intriguing and can be termed "nematic" superconductivity in analogy to nematic liquid-crystal phases. Here, based on specific-heat measurements of the single-crystalline CuxBi2Se3 under accurate magnetic-field-direction control, we report thermodynamic evidence for nematic superconductivity, namely, clear two-fold-symmetric behavior in a trigonal lattice. The results indicate realization of an "odd-parity nematic" state, feasible only by macroscopic quantum condensates and distinct from nematic states in liquid crystals. The results also confirm topologically non-trivial superconductivity in CuxBi2Se3.