Magnetic excitations and dynamics of the honeycomb iridate H3LiIr2O6

Alberto De La Torre

In the search for realizations of Quantum Spin Liquids (QSL), it is essential to understand the interplay between inherent structural disorder and long-range spin entanglement. H3LiIr2O6 is regarded as a spin liquid proximal to the Kitaev-limit in which bond disorder and stacking faults are known to be present [1]. These sources of random disorder have been invoked to account for the non-zero NMR relaxation rate and divergent specific heat, which are not expected within the Kitaev QSL model [2]. As such, the nature of H3LiIr2O6 remains unknown. Resonant inelastic X-ray scattering (RIXS) is the only technique able to resolve the magnetic excitations in iridium base Kitaev materials and is amenable to being extended into the time domain. In this talk, I will show that a broad bandwidth and momentum-independent continuum of magnetic excitations characterize the low-temperature low-energy excitations in H3LiIr2O6. Our data support an interpretation of H3LiIr2O6 as a disordered topological spin liquid in close proximity to bond-disordered versions of the KQSL [3]. I will also discuss preliminary time-resolved RIXS data in the context of Floquet engineering of magnetic exchange in Kitaev materials.

[1] Kitagawa et al., Nature 554, 341 (2018)
[2] Knoelle et al., Phys. Rev. Lett. 122, 047202 (2019)
[3] de la Torre et al., submitted