NMR Evidence for a Magnetic Soliton Lattice in the High-Field Phase of CuGeO3

We present copper NMR spectra obtained in the high magnetic field phase of the inorganic spin-Peierls compound CuGe${\mathrm{O}}_3$. In the whole range 13-17 T, the observed line shapes bring clear evidence for the existence of a static incommensurate distribution of the local spin density $S_z\mathrm{}\left(i\right)\mathrm{}$ corresponding to a magnetic soliton lattice. The absolute value of $S_z$ at the top of a soliton is found equal to 0.065 at 1.4 K and 16.3 T. The temperature dependence of the amplitude of the local spin distribution is proportional to ${(1-\frac{T}{T_c})}^{0.32}$.