Low Temperature Physics

Magnetic field pulse and abrupt change dynamics of a rhombohedric paramagnet

Andrei A. Zvyagin, G. A. Zvyagina

Published Jun 1, 2025• 0 citations

Abstract

The response of the quantum paramagnet with rhombohedric symmetry to the pulse and abrupt change (quantum quench) of the external magnetic field applied along z direction is calculated analytically. It is shown that the pulse and the quench produce oscillations of the magnetic moment of the paramagnet determined by the magnitude of the pulse or quench and the duration of the pulse (or time for the quench). It is also shown that not all energy levels of the paramagnet take part in the response. Our results can be applied for the description of response of qudits based on paramagnetic ions to gates in quantum computers. Response of the rhombohedric rare-earth alumoborate to the pulse of the magnetic field is calculated.

DOI: 10.1063/10.0036745

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