Thermodynamics of a spin-1/2 XYZ Heisenberg chain with a Dzyaloshinskii-Moriya interaction
We study the thermodynamics of an XYZ Heisenberg chain with Dzyaloshinskii-Moriya interaction, which describes the low-energy behaviors of a one-dimensional spin-orbit-coupled bosonic model in the deep insulating region. The entropy and the specific heat are calculated numerically by the quasi-exact transfer-matrix renormalization group. In particular, in the limit $U^\prime/U\rightarrow\infty$, our model is exactly solvable and thus serves as a benchmark for our numerical method. From our data, we find that for $U^\prime/U>1$ a quantum phase transition between an (anti)ferromagnetic phase and a Tomonaga-Luttinger liquid phase occurs at a finite $θ$, while for $U^\prime/U<1$ a transition between a ferromagnetic phase and a paramagnetic phase happens at $θ=0$. A refined ground-state phase diagram is then deduced from their low-temperature behaviors. Our findings provide an alternative way to detect those distinguishable phases experimentally.