- Letter
Conservation of angular momentum in an elastic medium with spins
Phys. Rev. B 103, L100412 – Published 29 March, 2021
DOI: https://doi.org/10.1103/PhysRevB.103.L100412
Abstract
Exact conservation of the angular momentum is worked out for an elastic medium with spins. The intrinsic anharmonicity of the elastic theory is shown to be crucial for conserving the total momentum. As a result, any spin-lattice dynamics inevitably involves multiphonon processes and interaction between phonons. This makes transitions between spin states in a solid fundamentally different from transitions between atomic states in a vacuum governed by linear electrodynamics. Consequences for using solid-state spins as qubits are discussed.
