English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

An important and continuing theme of modern solid state physics is therealization of exotic excitations in materials (e.g. quasiparticles) that haveno analogy (or have not yet been observed) in the actual physical vacuum offree space. Although they are not fundamental particles, such quasiparticles doconstitute the most basic description of the excited states of the "vacuum" inwhich they reside. In this regard the magnetic textures of the excited statesof spin ices, magnetic pyrochlore oxides with dominant Ising interactions, areproposed to be modeled as effective magnetic charge monopoles. Recent inelasticneutron scattering experiments have established the pyrochlore materialYb$_2$Ti$_2$O$_7$ (YbTO) as a quantum spin ice, where in addition to the Isinginteractions there are substantial transverse terms that may induce quantumdynamics and - in principle - coherent monopole motion. Here we report acombined time domain terahertz spectroscopy (TDTS) and microwave cavity studyof YbTO to probe its complex dynamic magnetic susceptibility. We find that theform of the susceptibility is consistent with monopole motion and a magneticmonopole conductivity can be defined and measured. Using the unique phasesensitive capabilities of these techniques, we observe a sign change in thereactive part of the magnetic response. In generic models of monopole motionthis is only possible through introducing inertial effects, e.g. a massdependent term, to the equations of motion. Analogous to conventional electriccharge systems, measurement of the conductivity's spectral weight allows us toderive a value for the magnetic monopole mass, which we find to beapproximately 1800 electron masses. Our results establish the magneticmonopoles of quantum spin ice as true coherently propagating quasiparticles ofthis system.

A Measure of Monopole Inertia in the Quantum Spin Ice Yb$_2$Ti$_2$O$_7$