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arXiv · 2503.09751

Light Drag in a Cavity Magnomechanics

Amjad Sohail·Hazrat Ali·Khalid Naseer·Rizwan Ahmed
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Abstract

The term "light dragging" describes how the trajectory of light changes as it travels through a moving medium. This phenomenon facilitates the precise detection of incredibly slow speeds of light, which is widely used in quantum gate operations, state transfer, and quantum memory implementations, etc. To the best of our knowledge, this is the first time we have proposed the existence of a light-dragging effect in a magnomechanical system (MMS). The origin of this crucial element stems from nonlinear dipole and magnetostrictive interactions in MMS. Magnomechanical characteristics such as magnon-photon and magnon-phonon couplings have a strong impact on both refractive and group index profile spectra. We also explore that lateral light drag shows a strong dependence on detuning by altering the amplitude and direction of the translational velocity. This enabled us to alter the light's propagation within the magnomechanical system from superluminal to subluminal and vice versa by adjusting the probe's detuning. The ability to control and manipulate the light drag through the MMS could be helpful in designing novel devices with improved functionality at the microscopic scale.

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Amjad Sohail, Hazrat Ali, Khalid Naseer, Rizwan Ahmed. 2025-03-12. Light Drag in a Cavity Magnomechanics. https://arxiv.org/abs/2503.09751

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