Magnetic properties of the Ising-like rare earth pyrosilicate: D-Er2Si2O7. (2nd August 2021)

• Record Type: Journal Article
• Authors: Hester, Gavin; DeLazzer, T N; Yahne, D R; Sarkis, C L; Zhao, H D; Rivera, J A Rodriguez; Calder, S; Ross, K A
• Is Part Of: Journal of physics. Volume 33:Number 40(2021)
• Publication Date: 2021-08-02
• Subjects: pyrosilicate -- rare earth magnetism -- Ising model -- inelastic neutron scattering; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/ac136a
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: Ising-like spin-1/2 magnetic materials are of interest for their ready connection to theory, particularly in the context of quantum critical behavior. In this work we report detailed studies of the magnetic properties of a member of the rare earth pyrosilicate family, D-Er2 Si2 O7, which is known to display a highly anisotropic Ising-like g -tensor and effective spin-1/2 magnetic moments. We used powder neutron diffraction, powder inelastic neutron spectroscopy (INS), and single crystal AC susceptibility to characterize its magnetic properties. Neutron diffraction enabled us to determine the magnetic structure below the known transition temperature ( T N = 1.9 K) in zero field, confirming that the magnetic state is a four-sublattice antiferromagnetic structure with two non-collinear Ising axes, as was previously hypothesized. Our powder INS data revealed a gapped excitation at zero field, consistent with anisotropic (possibly Ising) exchange. An applied field of 1 T produces a mode softening, which is consistent with a field-induced second order phase transition. To assess the relevance of D-Er2 Si2 O7 to the transverse field Ising model, we performed AC susceptibility measurements on a single crystal with the magnetic field oriented in the direction transverse to the Ising axes. This revealed a transition at 2.65 T at 0.1 K, a field significantly higher than the mode-softening field observed by powder INS, showing that the field-induced phase transitions are highly field-direction dependent as expected. These measurements suggest that D-Er2 Si2 O7 may be a candidate for further exploration related to the transverse field Ising model.