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arXiv · 2408.02186

Spectroscopic Feature of Quantum Many-Body Scar States

Wenjie Wei·Long Zhang
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Abstract

We study the dynamical correlations of nonintegrable systems with quantum many-body scar (QMBS) states generated by a ladder operator. The spectral function of the ladder operator has an exact $\delta$-function peak induced by the QMBS states. As a concrete example, we show that in the one-dimensional (1D) spin-$1$ Affleck-Kennedy-Lieb-Tasaki model, the spectral function of two-magnon excitations exhibits a characteristic bow-tie shape composed of a $\delta$-function resonance peak at momentum $k=\pi$ and a continuum spectrum elsewhere. The two-magnon excitations can be observed with the resonant inelastic X-ray scattering spectroscopy on quasi-1D nickelates and other spin-$1$ antiferromagnetic materials, thus it paves the way to detecting the (approximate) QMBS states in realistic materials.

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Wenjie Wei, Long Zhang. 2024-08-05. Spectroscopic Feature of Quantum Many-Body Scar States. https://doi.org/10.1088/0256-307x%2F42%2F2%2F020502

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