Topological Magnon Band Crossing in Y_{2}Ir_{2}O_{7}

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Topological magnonic materials offer potential for dissipationless spintronic devices.
• Pyrochlore iridates are theoretically promising for topological magnon bands, but experimental evidence is lacking.

Purpose of the Study:

• To experimentally investigate the existence of topological magnon bands in Y$_{2}$Ir$_{2}$O$_{7}$.
• To explore pyrochlore iridates as a platform for tunable magnon band topology.

Main Methods:

• Utilized Raman spectroscopy to measure single-magnon excitations and phonon shifts in Y$_{2}$Ir$_{2}$O$_{7}$.
• Performed tight-binding model calculations incorporating phonon data to determine spin Hamiltonian parameters.

Main Results:

• Confirmed Y$_{2}$Ir$_{2}$O$_{7}$ possesses a nontrivial magnon band topology.
• Identified key spin Hamiltonian parameters from experimental data and theoretical modeling.
• Demonstrated a magnon band topology distinct from other pyrochlore iridates.

Conclusions:

• Pyrochlore iridates can be engineered to achieve tailored magnon band topology.
• Raman spectroscopy is an effective tool for probing magnon band topology in materials.