Decoupling of static and dynamic criticality in a driven Mott insulator
Abstract
Strongly driven antiferromagnetic Mott insulators have the potential to exhibit exotic transient phenomena that are forbidden in thermal equilibrium. However, such far-from-equilibrium regimes, where conventional time-dependent Ginzburg-Landau descriptions fail, are experimentally challenging to prepare and to probe especially in solid state systems. Here we use a combination of time-resolved second harmonic optical polarimetry and coherent magnon spectroscopy to interrogate n-type photo-doping induced ultrafast magnetic order parameter dynamics in the antiferromagnetic Mott insulator Sr₂IrO₄. We find signatures of an unusual far-from-equilibrium critical regime in which the divergences of the magnetic correlation length and relaxation time are decoupled. This violation of conventional thermal critical behavior arises from the interplay of photo-doping and non-thermal magnon population induced demagnetization effects. Our findings, embodied in a non-equilibrium phase diagram, provide a blueprint for engineering the out-of-equilibrium properties of quantum matter, with potential applications to terahertz spintronics technologies.
Additional Information
© The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Received 23 November 2021; Accepted 19 January 2022; Published 04 February 2022. We thank L. Balents, A. Cavalleri, S. K. Cushing, E. Demler, S. Di. Matteo, M. Endres, B. Fine, N. Gedik, D. Kennes, O. Mehio, H. Ning, M. Norman, and M. Sentef for useful discussions. This work is supported by ARO MURI Grant No. W911NF-16-1-0361. D.H. also acknowledges support for instrumentation from the David and Lucile Packard Foundation and from the Institute for Quantum Information and Matter (IQIM), an NSF Physics Frontiers Center (PHY-1733907). A.d.l.T. acknowledges support from the Swiss National Science Foundation through an Early Postdoc Mobility Fellowship (P2GEP2165044). M.B. acknowledges support from the Alexander von Humboldt foundation. N.J.L. acknowledges support from an IQIM Fellowship. G.C. acknowledges NSF support via a grant DMR-1712101. Data availability: All relevant data presented in this paper are available from the corresponding author upon reasonable request. Author Contributions: X.C., S.D.W., and G.C. synthesized and characterized the Sr2IrO4 crystals. A.d.l.T., K.L.S., and I.P. performed the SHG-RA measurements. J.W.H., L.Z., and A.d.l.T. built the SHG-RA apparatus. G.Z. and R.D.A. performed the MOKE measurements. M.B., Y.B., and G.R. performed the Langevin theory calculations. A.d.l.T., N.J.L., and D.H. analyzed the data. A.d.l.T. and D.H. wrote the paper with input from all authors. The authors declare no competing interests. Communications Physics thanks the anonymous reviewers for their contribution to the peer review of this work.Attached Files
Published - s42005-022-00813-6.pdf
Submitted - 2112.08397.pdf
Supplemental Material - 42005_2022_813_MOESM1_ESM.pdf
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Additional details
- Eprint ID
- 112905
- Resolver ID
- CaltechAUTHORS:20220113-234606083
- W911NF-16-1-0361
- Army Research Office (ARO)
- David and Lucile Packard Foundation
- Institute for Quantum Information and Matter (IQIM)
- PHY-1733907
- NSF
- P2GEP2165044
- Swiss National Science Foundation (SNSF)
- Alexander von Humboldt Foundation
- DMR-1712101
- NSF
- Created
-
2022-01-14Created from EPrint's datestamp field
- Updated
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2022-02-10Created from EPrint's last_modified field
- Caltech groups
- Institute for Quantum Information and Matter