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Specific heat and muon spin resonance measurements in Gd(hfac)3NITiPr molecular magnetic chains: indications for a chiral phase without long range helical order

A. Lascialfari·R. Ullu·M. Affronte·F. Cinti·A. Caneschi·D. Gatteschi·D. Rovai·M. G. Pini·A. Rettori
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Abstract

Low temperature specific heat $C(T)$ and zero-field muon spin resonance ($μ^+$SR) measurements were performed in Gd(hfac)$_3$NITiPr, a quasi one-dimensional molecular magnet with competing nearest neighbor and next-nearest neighbor intrachain exchange interactions. The specific heat data exhibit a $λ$-peak at $T_0$=2.08$\pm$0.01K that disappears upon the application of a 5 Tesla magnetic field. Conversely, the $μ^+$SR data do not present any anomaly at $T\approx 2$ K, proving the lack of divergence of the two-spin correlation function as required for usual three-dimensional (3D) long range helical order. Moreover, no muon spin precession can be evinced from the $μ^+$SR asimmetry curves, thus excluding the presence of a long range ordered magnetic lattice. These results provide indications for a low $T$ phase where chiral order is established in absence of long range helical order.

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A. Lascialfari, R. Ullu, M. Affronte, F. Cinti, A. Caneschi, D. Gatteschi, D. Rovai, M. G. Pini, A. Rettori. 2003-02-17. Specific heat and muon spin resonance measurements in Gd(hfac)3NITiPr molecular magnetic chains: indications for a chiral phase without long range helical order. https://doi.org/10.1103/physrevb.67.224408

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