Physical properties in the normal and superconducting (SC) state are investigated with ${}^{125}\mathrm{Te}$-nuclear magnetic resonance (NMR) measurements in a quasicrystal ${\left({\mathrm{Ta}}_{0.95}{\mathrm{Cu}}_{0.05}\right)}_{1.6}\mathrm{Te}$, which was a recently discovered superconductor with the SC transition temperature $T_{\mathrm{c}}=0.94 \mathrm{K}$. The nuclear spin-lattice relaxation rate $1/T_1$ shows a coherence peak just below $T_{\mathrm{c}}$, followed by an exponential decrease down to 0.1 K. The overall temperature dependence of $1/T_1$ is in good agreement with an $s$-wave SC model with an SC gap slightly smaller than the BCS value. However, the coherence peak is unusually small, which may be attributable to a reduced Bogoliubov peak theoretically predicted for quasicrystals. Furthermore, ${}^{125}\mathrm{Te}\text{−}\mathrm{NMR}$ spectra show marginal shift and almost no linewidth broadening below $T_{\mathrm{c}}$, revealing unusual superconducting responses in this quasicrystal.

Close

PrevNext

View figure in article

• Superconductivity
• 2-dimensional systems
• Quasicrystals
• Nuclear magnetic resonance