Experimental and theoretical delimitation of the quasi-1D Tomonaga-Luttinger-liquid regime in a spin-1 field-induced antiferromagnet

Abstract Through a combination of experimental and theoretical techniques, we study the spin-1 field-induced antiferromagnet NiCl2–4SC(NH2)2, (DTN). Specifically, we use magnetic susceptibility and specific heat measurements, combined with Quantum Monte-Carlo calculations to delimit the quasi-1D Tomonaga-Luttinger-liquid region just above the BEC phase diagram and extend our studies to higher temperatures, where the spin interactions become negligible. This also allows us to verify some discrepancies in the value of the single-ion anisotropy parameter D, which are not well understood yet.