R.V. Pisareva aIoffe Institute, ul. Polytekhnicheskaya 26, St. Petersburg, 194021, Russian Federation bMoscow State Institute of Radio Engineering, Electronics, and Automatics (Technical University), prosp. Vernadskogo 78, Moscow, 117454, Russian Federation cRadboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, Nijmegen, 6525 AJ, The Netherlands
In the last decade, a new area of research, referred to as femtomagnetism, has developed within the field of magnetism, which studies the excitation and control of magnetic medium dynamics on timescales comparable to or even much shorter than those of the spin-lattice, spin-orbit, and exchange interactions. Among many femtomagnetic processes studied by now, the optomagnetic interaction of femtosecond laser pulses with media is of particular interest. This interaction is based on nondissipative Raman-type mechanisms and enables coherent spin dynamics to be efficiently and selectively excited and its parameters to be controlled. This review considers the key features of ultrafast optomagnetic phenomena and how they relate to magneto-optical effects. A number of experimentally observed examples of ultrafast spin dynamics excited via optomagnetic inverse Faraday and Cotton—Mouton effects are considered, and their microscopical nature is discussed. An experimental example is given demonstrating that combining ultrafast optomagnetic phenomena with other laser-induced processes allows magnetization to be controlled on a picoseconds time scale.