Giant peak of the Inverse Faraday effect in the band gap of magnetophotonic crystal

• Published in: arXiv.org 2018-05
• Main Authors: Kozhaev, Mikhail A, Chernov, Alexander I, Sylgacheva, Daria A, Shaposhnikov, Alexander N, Prokopov, Anatoly R, Berzhansky, Vladimir N, Zvezdin, Anatoly K, Belotelov, Vladimir I
• Format: Article
• Language: English
• Subjects: Angular momentum; Band gap; Crystals; Data processing; Dependence; Energy gap; Faraday effect; Film thickness; Lasers; Magnetic films; Quantum phenomena; Spintronics; Substrates
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1805.04862

Optical impact on the spin system in a magnetically ordered medium provides a unique possibility for local manipulation of magnetization at subpicosecond time scales that is very promising for magnetic data processing and other magnonics applications. One of the mechanisms of the optical manipulation is related to the inverse Faraday effect (IFE). Usually the IFE is observed in crystals and magnetic films on a substrate. Here we demonstrate the IFE induced by fs-laser pulses in the magnetic film inside the magnetophotonic crystal. Spectral dependence of the IFE on the laser pulse wavelength in the band gap of the magnetophotonic crystal has a sharp peak leading to a significant enhancement of the IFE. This phenomenon is explained by strong confinement of the electromagnetic energy and angular momentum within the magnetic film. Calculated near field distribution of the IFE effective magnetic field indicates its subwavelength localization within 30 nm along the film thickness. These excited volumes can be shifted along the sample depth via e.g. changing frequency of the laser pulses. The obtained results open a way for the new applications in the areas of ultrafast spintronics and quantum information processing.