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arXiv · 2503.16020

Skyrmionic Schrödinger cat states in monoaxial chiral magnets

Stefan Liscak·Andreas Haller·Andreas Michels·Thomas L. Schmidt·Vladyslav M. Kuchkin
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Abstract

We study the low-energy excitation spectra of a spin-1/2 quantum Heisenberg model with a monoaxial Dzyaloshinskii-Moriya interaction. Using the density matrix renormalization group method, our analysis reveals a degeneracy between skyrmion and antiskyrmion states, enabling the formation of a mesoscopic Schrödinger cat state - a quantum superposition of these topologically distinct textures. To characterize this nontrivial state, we compute two-point spin correlation functions, highlighting signatures accessible via neutron scattering experiments. Furthermore, we demonstrate that applying a magnetic field gradient induces a coherent time evolution of the cat state, offering a controllable mechanism for its manipulation. These findings provide a framework for the detection of skyrmionic Schrödinger cat states in quantum magnets.

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Stefan Liscak, Andreas Haller, Andreas Michels, Thomas L. Schmidt, Vladyslav M. Kuchkin. 2025-07-22. Skyrmionic Schrödinger cat states in monoaxial chiral magnets. https://doi.org/10.1103/842q-ghyt

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