Quantum Depinning of a Magnetic Skyrmion

Abstract

We investigate the quantum depinning of a weakly driven skyrmion out of an impurity potential in a mesoscopic magnetic insulator. For small barrier height, the Magnus force dynamics dominates over the inertial one, and the problem is reduced to a massless charged particle in a strong magnetic field. The universal form of the WKB exponent, the rate of tunneling, and the crossover temperature between thermal and quantum tunneling is provided, independently of the detailed form of the pinning potential. The results are discussed in terms of macroscopic parameters of the insulator Cu2OSeO3 and various skyrmion radii. We demonstrate that small enough magnetic skyrmions, with a radius of ~ 10 lattice sites, consisting of some thousands of spins, can behave as quantum objects at low temperatures in the mK regime.

6 pages, 3 figures

References in corpus (6)

• Advances in the Physics of Magnetic Skyrmions and Perspective for Technology
• Inertia and chiral edge modes of a skyrmion magnetic bubble
• Capturing of a Magnetic Skyrmion with a Hole
• The quantum origins of skyrmions and half-skyrmions in Cu2OSeO3
• A mechanism to pin skyrmions in chiral magnets
• Macroscopic quantum tunneling and quantum-classical phase transitions of the escape rate in large spin systems

Cited by in corpus (6)

• Quantum magnonics: when magnon spintronics meets quantum information science
• Skyrmion Qubits: A New Class of Quantum Logic Elements Based on Nanoscale Magnetization
• Skyrmion Qubits: Challenges For Future Quantum Computing Applications
• Colloquium: Quantum Properties and Functionalities of Magnetic Skyrmions
• Skyrmion Helicity: Quantization and Quantum Tunneling Effects
• Topological dipoles of quantum skyrmions