Spin Gap in the Single Spin-1/2 Chain Cuprate Sr${}_{1.9}$Ca${}_{0.1}$CuO${}_3$

F. Hammerath, E. M. Brüning, S. Sanna +7

We report ${}^{63}$Cu nuclear magnetic resonance and muon spin rotation measurements on the S=1/2 antiferromagnetic Heisenberg spin chain compound Sr${}_{1.9}$Ca${}_{0.1}$CuO${}_3$. An exp…