Spin dynamics in the quantum spin system KCu5V3O13

Abstract The complex Oxo-Cu-vanadate KCu 5 V 3 O 13 with 5 independent Cu-sites (s= 1 2 ) per unit cell has an exchange topology described as a ladder of spin tetrahedra or triangles. Magnetic susceptibility measurements on single crystals show a steplike anomaly at 213 K and an antiferromagnetic transition at 7.5 K . ZF μ SR reveals only nuclear relaxation above 10 K and two spontaneous precession signals in the long range ordered regime. Below 3.7 K , a spin reorientation leads to a broad frequency distribution typical for an incommensurate spin structure.