August 11-14th at the Crowne Plaza Hotel in downtown Knoxville, TN

Neutron scattering investigation of Tb$^{3+}$ crystal fields in magnetoelastic TbSi

Not scheduled

20m

Crowne Plaza Knoxville

Poster Only

Speaker

Sierra Diller (Georgia Tech)

Description

TbSi is an FeB-type compound exhibiting complex antiferromagnetic behavior with two first-order and one second-order phase transitions. Below 35 K, it exhibits a planar AFM structure then transitions into an incommensurate phase between 35 and 39 K before becoming commensurate again up to the Néel temperature, $T_N$ = 57 K[1]. We measured the temperature-dependent crystal field softening, which is associated with the magnetic structure transition via powder inelastic neutron scattering measurements at ARCS, SNS. The polycrystalline averaged crystal field transitions from a gapped dispersion-like feature at $T$ = 10 K to a smooth ungapped feature at $T$ = 37 K, and paramagnet-like feature above 50 K. Magnetization measurements and heat capacity studies have shown a unique hysteresis of the magnetic transition[2], and we investigated the magnetic structure transitions via quasi-continuous heating neutron powder diffraction from $T$ = 34 to 40 K at POWGEN, SNS.

Research was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division (BES-MSED). This work was supported in part by the U.S. Department of Energy, Office of Science, Office of Workforce Development for Teachers and Scientists (WDTS) under the Science Undergraduate Laboratory Internships Program (SULI) (S.D.). A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. The beam time was allocated at ARCS and POWGEN on proposal numbers IPTS-33695 and ITPS-33763, respectively.

[1] Schobinger-Papamantellos, P., Janssen, T. and Buschow, K.H.J., Thermal variation of incommensurate magnetic phases in TbSi as observed by neutron diffraction. Journal of magnetism and magnetic materials, 127(1-2), p.115-128 (1993).

[2] Kumar, A., Singh, P., Doyle, A., Schlagel, D.L. and Mudryk, Y., Multiple magnetic interactions and large inverse magnetocaloric effect in TbSi and TbSi0.6Ge0.4. Physical Review B, 109(21), p.214410 (2024).