Melting of spin ice state and development of fifth order susceptibility with magnetic field in pyrochlore Tb₂Sn₂O₇

Abstract

Pyrochlores offer an ideal playground to investigate the magnetic ground state of frustrated magnetic systems. In this class of materials, competition between various magnetic interactions remains frustrated and prevents an ordered magnetic state at low temperatures. Tb2Sn2O7 has recently attracted significant attention due to its ordered spin-ice state. Additionally, in such systems, application of external magnetic field might result in exotic magnetic states. Our current investigation on Tb2Sn2O7 reveal the presence of a new phase associated with fifth order susceptibility at low temperatures and high magnetic fields. In this compound, at zero fields, for a stabilized spin-ice state, the singlet-singlet state separated by δ play an imperative role. Under magnetic fields, δ increases and the Zeeman energy associated with the magnetic anisotropy is believed to get enhanced; which can be the key ingredient for evolution of higher-order moments, above 10 kOe, in this compound.

Collective magnetic state induced by charge disorder in the non-Kramers rare-earth pyrochlore Tb$_{2}$ScNbO$_{7}$

“…3d. At 90 mK, the magnetization does not saturate up to 8 T, and reaches 5.3 µ B per Tb 3+ ion, lower than the free ion value g J J = 9 µ B , but close to the values reported for other Tb pyrochlores [28,38,[40][41][42][43][44]. It is in agreement with the calculated ground state doublet wavefunctions for the 13 charge distributions, prominently constituted of |J z = ±5 .…”

Evolution of field induced magnetic phase attributed to higher order magnetic moments in TbVO4

“…Hence, it can be inferred that at higher magnetic fields, Zeeman effect comes into play resulting in an increment in the splitting of the doublet ground state, which in turn, is believed to be responsible for the development of higher order moments at low temperatures. Furthermore, we have used a theoretical model 43 to support our experimental observations. Mainly, our model emphasizes on two aspects: (i) Contribution of out-of-plane component of g-tensor ( g ⊥ ) at higher fields.…”

“…This enhanced separation is believed to be responsible for the evolution of this new magnetic phase of higher order moments 40 . In order to support our experimental observation, we have used a theoretical model which calculates the δ as a function of magnetic field 43 , discussed in the next section. Furthermore, to check the stability of the field induced magnetic phase, magnetic free energy F is studied which can be written in the term of H and M up to sixth order 42 .…”