Theoretical investigation of the behavior of CuSe2O5 compound in high magnetic fields

• We investigate thermodynamic properties of CuSe2O5 at high magnetic fields.
• The behavior of CuSe2O5 above Neel temperature (TN) is like spin chains.
• This compound above TN is described by1D spin-1/2 XXZ Heisenberg model.
• There is one quantum critical field in this compound at Hc=2300 K Oe.
• Indications on thermodynamic curves confirm the event of such a phase transition.
• Wilson ratio (Rw) at fixed temperature remains almost constant in the LL phase.
• Rw exhibits anomalous enhancement near the quantum critical field.

Based on the analytical and numerical approaches, we investigate thermodynamic properties of CuSe2O5 compound at high magnetic fields which is a candidate for the strong intra-chain interaction in quasi one-dimensional (1D) quantum magnets. Magnetic behavior of the system can be described by the 1D spin-1/2 XXZ model in the presence of the Dzyaloshinskii–Moriya (DM) interaction. Under these circumstances, there is one quantum critical field in this compound. Below the quantum critical field the spin chain system is in the gapless Luttinger liquid (LL) regime, whereas above it one observes a crossover to the gapped saturation magnetic phase. Indications on the thermodynamic curves confirm the occurrence of such a phase transition. The main characteristics of the LL phase are gapless and spin–spin correlation functions decay algebraic. The effects of zero-temperature quantum phase transition are observed even at rather high temperatures in comparison with the counterpart compounds. In addition, we calculate the Wilson ratio in the model. The Wilson ratio at a fixed temperature remains almost independent of the field in the LL region. In the vicinity of the quantum critical field, the Wilson ratio increases and exhibits anomalous enhancement.