Low-temperature studies of a 2D Quantum Heisenberg Antiferromagnet

A recent inelastic neutron scattering experiment of a 2D Quantum Heisenberg Antiferromagnet (2DQHAF) in an applied field [1] revealed novel features in the energy spectrum but the field was limited to \textless 0.3 H$_{\mathrm{SAT}}$ due to the exchange strength (J $=$ 17.5 K) of the material under study. (Quinolinium)$_{2}$CuBr$_{4}$$\cdot$2H$_{2}$O is known [2] to be a molecular-based version of a strongly 2D QHAF with a significantly smaller exchange strength of 6.2 K and a saturation field of 15 T. We report the low-temperature properties (T \textless\ 1.8 K) of (Quinolinium)$_{2}$CuBr$_{4}$$\cdot$2H$_{2}$O and discuss its applicability for further investigations.\\[4pt] [1] N. Tsyrulin, T. Pardina, R. R. P. Singh et al, \textit{Phys. Rev. Lett}. \textbf{102}, 197201: 1-4 (2009).\\[0pt] [2] R. T. Butcher, M. M. Turnbull, C. P. Landee et al, \textit{Inorg. Chem.} \textbf{49}, 427-434 (2010).