Spin-Peierls and spin-glass phases in pure and doped CuGeO3: a μSR study

We have conducted μSR measurements in pure and Zn-doped CuGeO3. The pure compound does not have static magnetic moments between 3 and 100 K, in agreement with its earlier proposed spin-Peierls structure. In Cu0.96Zn0.04GeO3, we found a spin-glass-like freezing of a small portion of Cu spins, presumably near the chain-cutting Zn atoms, occurring gradually between 3.5 and 6 K.