1 research outputs found
Magnetic order and spin fluctuations in the spin liquid TbSnO.
We have studied the spin liquid TbSnO by neutron diffraction and specific heat measurements. Below about 2 K, the magnetic correlations change from antiferromagnetic to ferromagnetic. Magnetic order settles in two steps, with a smeared transition at 1.3(1) K then an abrupt transition at 0.87(2) K. A new magnetic structure is observed, not predicted by current models, with both ferromagnetic and antiferromagnetic character. It suggests that the spin liquid degeneracy is lifted by dipolar interactions combined with a finite anisotropy along axes. In the ground state, the Tb ordered moment is reduced with respect to the free ion moment (9 ). The moment value of 3.3(3) deduced from the specific heat is much smaller than derived from neutron diffraction of 5.9(1) . This difference is interpreted by the persistence of slow collective magnetic fluctuations down to the lowest temperatures