Ultrafast Mid Infrared Pump-Optical Kerr Probe of Correlated Mott-Hubbard Antiferromagnets

ORAL

Abstract

We utilize intense ultrafast mid-infrared (mid-IR) circularly polarized pump pulses to preferentially excite spin degrees of freedom through coherent two-magnon excitation as measured via the magneto-optic Kerr effect using 800 nm pulses. Our previous results [1] on the spin-orbit coupled Mott-Hubbard insulator (MHI) Sr2IrO4 indicate that magnon generation using mid-IR pulses is nearly an order of magnitude more efficient in comparison to above gap doublon generation. To clarify the potential of mid-IR pulses for coherent magnon generation, we are investigating the canonical MHI nickel oxide which serves as a well characterized material for comparison with theoretical predictions [2]. This presentation will provide an update on these experiments with a view towards mode-selective spin excitation in quantum materials.
[1] Gu-Feng Zhang, Xiang Chen, Urban F.P. Seifert, Jingdi Zhang, Kevin Cremin, Leon Balents, Stephen D. Wilson and Richard D. Averitt. “Ultrafast magnetic control in a spin-orbit coupled iridate.” Manuscript in Preparation.
[2] Seifert, Urban FP, and Leon Balents. "Optical excitation of magnons in an easy-plane antiferromagnet: Application to Sr 2 IrO 4." Physical Review B 100, no. 12 (2019): 125161.

*This work was supported by ARO Award No. W911NF-16-1-0361.

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Presenters

  • Mustafa G Ali

    • Department of Physics, University of California, San Diego

Authors

  • Mustafa G Ali

    • Department of Physics, University of California, San Diego

  • Kelson Kaj

    • University of California San Diego
    • Physics, University of California San Diego
    • Department of Physics, University of California, San Diego
    • University of California, San Diego

  • Varun Ramaprasad

    • Department of Physics, University of California, San Diego

  • Gufeng Zhang

    • Physics, University of California San Diego
    • Department of Physics, University of California, San Diego

  • Xiang Chen

    • Materials Department, University of California, Santa Barbara

  • Urban F. P. Seifert

    • Institut fur Theoretische Physik, Technische Universitat Dresden

  • Jingdi Zhang

    • Department of Physics, University of California, San Diego

  • Kevin A Cremin

    • Department of Physics, University of California, San Diego
    • University of California, San Diego

  • Leon Balents

    • Kavli Institute for Theoretical Physics, University of California, Santa Barbara
    • University of California, Santa Barbara

  • Stephen D. Wilson

    • Materials Department, UC Santa Barbara
    • Materials Department, University of California, Santa Barbara, California 93106-5050, USA
    • Materials, University of Santa Barbara
    • Materials Department, University of California, Santa Barbara

  • Richard Averitt

    • University of California, San Diego
    • University of California San Diego
    • UC San Diego
    • Physics, University of California San Diego
    • Department of Physics, University of California, San Diego
    • University of California