Spinon Phonon Interaction and Ultrasonic Attenuation in Quantum Spin Liquids

Several experimental candidates for quantum spin liquids have been discovered in the past few years which appear to support gapless fermionic S=1/2 excitations called spinons. The spinons may form a Fermi sea coupled to a U(1) gauge field, and may undergo a pairing instability. We show that despite...

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Bibliographic Details
Main Authors: Zhou, Yi, Lee, Patrick A.
Other Authors: Massachusetts Institute of Technology. Department of Physics
Format: Article
Language:en_US
Published: American Physical Society 2011
Online Access:http://hdl.handle.net/1721.1/64471
https://orcid.org/0000-0001-7809-8157
Description
Summary:Several experimental candidates for quantum spin liquids have been discovered in the past few years which appear to support gapless fermionic S=1/2 excitations called spinons. The spinons may form a Fermi sea coupled to a U(1) gauge field, and may undergo a pairing instability. We show that despite being charge neutral, the spinons couple to phonons in exactly the same way that electrons do in the long wavelength limit. Therefore, we can use sound attenuation to measure the spinon mass and lifetime. Furthermore, transverse ultrasonic attenuation is a direct probe of the onset of pairing because the Meissner effect of the gauge field causes a “rapid fall” of the attenuation at Tc [T subscript c] in addition to the reduction due to the opening of the energy gap. This phenomenon, well known in clean superconductors, may reveal the existence of the U(1) gauge field.