Novel magnetic field tuning of quantum spin excitations in a weakly coupled $S=$1/2 Heisenberg spin chain as seen from NMR

Long Ma, Z. Wang, L. Hu +3

We report our NMR study of the spin excitations in the quasi-one dimensional (1D) $S=1/2$ quantum magnet CH${}_3$NH${}_3$Cu(HCOO)${}_3$ lying in the 1D-3D dimensional crossover regime wi…