skip to main content


Title: Superconductivity in a Misfit Phase That Combines the Topological Crystalline Insulator Pb 1-xSn xSe with the CDW-Bearing Transition Metal Dichalcogenide TiSe 2

We report the characterization of the misfit compound (Pb 1-xSn xSe 2)1.16(TiSe 2) 2 for 0 ≤ x ≤ 0.6, in which a [100] rocksalt-structure bilayer of Pb1-xSnxSe, which is a topological crystalline insulator in bulk form, alternates with a double layer of the normally nonsuperconducting transition metal dichalcogenide TiSe 2. The x dependence of Tc displays a weak dome-like shape with a maximum Tc of 4.5 K at x = 0.2; there is only a subtle change in Tc at the composition where the trivial to topological transition occurs in bulk Pb1-xSnxSe. We present the characterization of the superconductor at x = 0.4, for which the bulk Pb1-xSnxSe phase is in the topological crystalline insulator regime. For this material, the Sommerfeld parameter γ = 11.06 mJ mol -1 K -2, the Debye temperature Θ D = 161 K, the normalized specific heat jump value ΔC/γT c = 1.38 and the electron-phonon constant value γ ep = 0.72, suggesting that (Pb 0.6Sn 0.4Se) 1.16(TiSe 2) 2 is a BCS-type weak coupling superconductor. This material may be of interest for probing the interaction of superconductivity with the surface states of a topological crystalline insulator.
 [1] ;  [2] ;  [3] ;  [1] ;  [1] ;  [4] ;  [1]
  1. Princeton Univ., NJ (United States)
  2. Brown Univ., Providence, RI (United States)
  3. Brookhaven National Lab. (BNL), Upton, NY (United States); Princeton Univ., NJ (United States)
  4. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0031-9015; R&D Project: PO016; KC0202020
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of the Physical Society of Japan
Additional Journal Information:
Journal Volume: 85; Journal Issue: 6; Journal ID: ISSN 0031-9015
Physical Society of Japan
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Topological insulator; Transition Metal Dichalcogenide; Superconductivity; Misfit phase
OSTI Identifier: