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arXiv · 2111.12514

Ultrafast control of spin-orbital separation probed with time-resolved RIXS

Aaron Müller·Francesco Grandi·Martin Eckstein
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Abstract

Quasi-one-dimensional systems exhibit many-body effects elusive in higher dimensions. A prime example is spin-orbital separation, which has been measured by resonant inelastic X-ray scattering (RIXS) in Sr$_2$CuO$_3$. Here, we theoretically analyze the time-resolved RIXS spectrum of Sr$_2$CuO$_3$ under the action of a time-dependent electric field. We show that the external field can reversibly modify the parameters in the effective $t-J$ model used to describe spinon and orbiton dynamics in the material. For strong driving amplitudes, we find that the spectrum changes qualitatively as a result of reversing the relative spinon to orbiton velocity. The analysis shows that in general, the spin-orbital dynamics in Mott insulators in combination with time-resolved RIXS should provide a suitable platform to explore the reversible control of many-body physics in the solid with strong laser fields.

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Aaron Müller, Francesco Grandi, Martin Eckstein. 2021-11-24. Ultrafast control of spin-orbital separation probed with time-resolved RIXS. https://doi.org/10.1103/physrevb.106.l121107

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