Observation of spin current in quantum spin liquid

TL;DR

This paper demonstrates that quantum spin liquids in spin-1/2 chains can generate and carry spin currents, evidenced by anisotropic negative spin Seebeck effect, opening new avenues for atomic-scale spin-current devices.

Contribution

It provides the first experimental evidence that spin liquids can support spin current flow in atomic channels, linking quantum fluctuation phenomena to spin transport.

Findings

Spin liquid in quantum chains generates spin current.

Observation of anisotropic negative spin Seebeck effect.

Potential for atomic-scale spin-current wiring.

Abstract

Spin liquid is a state of electron spins in which quantum fluctuation breaks magnetic ordering while maintaining spin correlation. It has been a central topic in magnetism because of its relevance to high-Tc superconductivity and topological states. However, utilizing spin liquid has been quite difficult. Typical spin liquid states are realized in one-dimensional spin systems, called quantum spin chains. Here, we show that a spin liquid in a spin-1/2 quantum chain generates and carries spin current via its long-range spin fluctuation. This is demonstrated by observing an anisotropic negative spin Seebeck effect along the spin chains in Sr2CuO3. The results show that spin current can flow even in an atomic channel owing the spin liquid state, which can be used for atomic spin-current wiring.