Field-induced partial disorder in a Shastry-Sutherland lattice

Area of Science:

• Condensed Matter Physics
• Magnetism
• Materials Science

Background:

• The Shastry-Sutherland lattice is a geometrically frustrated magnetic system.
• Neodymium (Nd) based compounds often exhibit complex magnetic ordering due to their electronic structure.
• Understanding magnetic order in low dimensions is crucial for developing novel magnetic materials.

Purpose of the Study:

• To determine the magnetic structure of BaNd2ZnS5 below its ordering temperature.
• To investigate the magnetic anisotropy and spin arrangement of Nd ions.
• To explore the magnetic phase transitions under an applied magnetic field.

Main Methods:

• Single crystal neutron diffraction was employed to identify the magnetic structure.
• Polarized neutron scattering was used to determine the nature of Nd spins.
• Magnetization measurements were performed at various temperatures and magnetic fields.

Main Results:

• A 2-Q antiferromagnetic order was identified below TN = 2.9 K.
• The magnetic structure consists of orthogonal Ising-like Nd spins.
• A metamagnetic transition was observed, decoupling two magnetic sublattices with distinct stripe orders.
• One sublattice order (q1) remained robust up to 6 T, while the other (q2) was suppressed at Hc ~1.7 T.

Conclusions:

• BaNd2ZnS5 exhibits a complex 2-Q antiferromagnetic state driven by Ising-like Nd spins.
• The applied magnetic field induces a selective suppression of one magnetic sublattice, leading to partial disorder.
• The constructed H-T phase diagram reveals temperature-dependent critical fields, offering insights into magnetic phase transitions in this material.