Degeneracy of the $1/8$ Plateau and Antiferromagnetic Phases in the Shastry-Sutherland Magnet ${\mathrm{TmB}}_{4}$

Degeneracy of the $1 / 8$ Plateau and Antiferromagnetic Phases in the Shastry-Sutherland Magnet ${TmB}_{4}$

Jennifer Trinh, Sreemanta Mitra, Christos Panagopoulos, Tai Kong, Paul C. Canfield, and Arthur P. Ramirez

Phys. Rev. Lett. 121, 167203 – Published 18 October 2018

Abstract

The $1 / 8$ fractional plateau phase ( $1 / 8$ FPP) in Shastry-Sutherland lattice (SSL) spin systems has been viewed an exemplar of emergence on an Archimedean lattice. Here we explore this phase in the Ising magnet ${TmB}_{4}$ using high-resolution specific heat ( $C$ ) and magnetization ( $M$ ) in the field-temperature plane. We show that the $1 / 8$ FPP is smoothly connected to the antiferromagnetic phase on ramping the field from $H = 0$ . Thus, the $1 / 8$ FPP is not a distinct thermodynamic ground state of ${TmB}_{4}$ . The implication of these results for Heisenberg spins on the SSL is discussed.

Received 26 December 2017

DOI:https://doi.org/10.1103/PhysRevLett.121.167203

Physics Subject Headings (PhySH)

Frustrated magnetism Metamagnetism Order parameters Specific heat

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Jennifer Trinh¹, Sreemanta Mitra^2,†, Christos Panagopoulos², Tai Kong^3,‡, Paul C. Canfield³, and Arthur P. Ramirez^1,*

¹University of California Santa Cruz, Santa Cruz, California 95064, USA
²Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371, Singapore
³Ames Laboratory, Iowa State University, Ames, Iowa 50011, USA

^*Corresponding author. apr@ucsc.edu
^†Present address: Department of Physics, Indian Institute of Science, Bangalore, 560012, India.
^‡Present address: Department of Chemistry, Princeton University, Princeton New Jersey, 08544, USA.