Spinon Heat Transport in the Three-Dimensional Quantum Magnet PbCuTe_{2}O_{6}

Area of Science:

• Condensed Matter Physics
• Quantum Magnetism

Background:

• Quantum spin liquids (QSLs) are exotic states of matter exhibiting quantum disorder at absolute zero.
• They feature emergent gauge fields and fractionalized quasiparticles, key to understanding novel quantum phenomena.

Purpose of the Study:

• To investigate the low-temperature thermal transport of the 3D S=1/2 hyperhyperkagome magnet PbCuTe_{2}O_{6}.
• To determine if its properties are consistent with a quantum spin liquid state.

Main Methods:

• Sub-kelvin thermal transport measurements were performed on PbCuTe_{2}O_{6}.
• Analysis focused on identifying charge-neutral fermionic contributions and their robustness.

Main Results:

• A significant charge-neutral fermionic contribution was observed in the thermal transport.
• This contribution aligns with itinerant fractionalized excitations forming a spinon Fermi surface.
• The QSL features remained robust against variations in sample quality and applied magnetic fields.

Conclusions:

• PbCuTe_{2}O_{6} exhibits key characteristics of a true quantum spin liquid.
• The observed thermal transport properties provide strong evidence for fractionalized excitations in a QSL state.
• Extrinsic effects were ruled out as explanations for the observed phenomena.