BaCo2V2O8 is a nice example of a quasi-one-dimensional quantum spin system that can be described in terms of Tomonaga-Luttinger liquid physics. This is explored in the present study where the magnetic field-temperature phase diagram is thoroughly est
ablished up to 12 T using single-crystal neutron diffraction. The transition from the Neel phase to the incommensurate longitudinal spin density wave (LSDW) phase through a first-order transition, as well as the critical exponents associated with the paramagnetic to ordered phase transitions, and the magnetic order both in the Neel and in the LSDW phase are determined, thus providing a stringent test for the theory.
