165 citations · 664 across the 22 of their papers we have counts for
22 papers
Spurious spin nutation modes arising from truncated memory effects
Markus Weißenhofer, Ritwik Mondal, M. S. Mrudul +1
Spin dynamics is conventionally treated as inertia-free. The inertial Landau-Lifshitz-Gilbert equation (iLLG) extends this with a second-order time derivative, predicting a high-fr…
Theory of tensorial magnetic inertia in terahertz spin dynamics
Subhadip Ghosh, Mikhail Cherkasskii, Igor Barsukov +1
Magnetic inertia has emerged as a possible way to manipulate ferromagnetic spins at a higher frequency e.g., THz. Theoretical treatments so far have considered the magnetic inertia…
Inertial spin waves in spin spirals
Mikhail Cherkasskii, Ritwik Mondal, Levente Rózsa
Inertial effects in spin dynamics emerge on picosecond time scales, giving rise to nutational excitations at THz frequencies. Here, we describe a general framework for investigatin…
Magnetization precession after non-collinear dual optical excitation
Sergii Parchenko, Davide Pecchio, Ritwik Mondal +2
We investigate the impact of non-collinear dual optical excitation on the magnetization precession in a permalloy thin film using two ultrashort laser pulses. By analyzing the magn…
Inertial effects in ultrafast spin dynamics
Ritwik Mondal, Levente Rózsa, Michael Farle +3
The dynamics of magnetic moments consist of a precession around the magnetic field direction and a relaxation towards the field to minimize the energy. While the magnetic moment an…
Inertial spin waves in ferromagnets and antiferromagnets
Ritwik Mondal, Levente Rózsa
Inertial effects in spin dynamics are theoretically predicted to emerge at ultrashort time scales, but their experimental signatures are often ambiguous. Here, we calculate the spi…
Theory of inertial spin dynamics in anisotropic ferromagnets
Mikhail Cherkasskii, Igor Barsukov, Ritwik Mondal +2
Recent experimental observation of inertial spin dynamics calls upon holistic reevaluation of the theoretical framework of magnetic resonance in ferromagnets. Here, we derive the s…
Spin pumping at terahertz nutation resonances
Ritwik Mondal, Akashdeep Kamra
We investigate spin pumping current injected by the nutation resonances of a ferromagnet or an antiferromagnet into an adjacent metal. Comparing the dc spin pumping current between…
Influence of inter-sublattice coupling on the terahertz nutation spin dynamics in antiferromagnets
Ritwik Mondal, Peter M. Oppeneer
Spin nutation resonance has been well-explored in one-sublattice ferromagnets. Here, we investigate the spin nutation in two-sublattice antiferromagnets as well as, for comparison,…
Theory of magnetic inertial dynamics in two-sublattice ferromagnets
Ritwik Mondal
The magnetic inertial dynamics have been investigated for one sublattice ferromagnets. Here, we develop the magnetization dynamics in two-sublattice ferromagnets including the intr…
Nutation in antiferromagnetic resonance
Ritwik Mondal, Sebastian Großenbach, Levente Rózsa +1
The effect of inertial spin dynamics is compared between ferromagnetic, antiferromagnetic and ferrimagnetic systems. The linear response to an oscillating external magnetic field i…
Terahertz spin dynamics driven by an optical spin-orbit torque
Ritwik Mondal, Andreas Donges, Ulrich Nowak
Spin torques are at the heart of spin manipulations in spintronic devices. Here, we examine the existence of an optical spin-orbit torque, a relativistic spin torque originating fr…
Dynamics of the relativistic electron spin in an electromagnetic field
Ritwik Mondal, Peter M. Oppeneer
A relativistic spin operator cannot be uniquely defined within relativistic quantum mechanics. Previously, different proper relativistic spin operators have been proposed, such as…
Terahertz spin dynamics driven by a field-derivative torque
Ritwik Mondal, Andreas Donges, Ulrike Ritzmann +2
Efficient manipulation of magnetization at ultrashort time scales is of particular interest for future technology. Here, we numerically investigate the influence of the so-called f…
Unified theory of magnetization dynamics with relativistic and nonrelativistic spin torques
Ritwik Mondal, Marco Berritta, Peter M. Oppeneer
Spin torques play a crucial role in operative properties of modern spintronic devices. To study current-driven magnetization dynamics, spin-torque terms providing the action of spi…
Generalisation of Gilbert damping and magnetic inertia parameter as a series of higher-order relativistic terms
Ritwik Mondal, Marco Berritta, Peter M. Oppeneer
The phenomenological Landau-Lifshitz-Gilbert (LLG) equation of motion remains as the cornerstone of contemporary magnetisation dynamics studies, wherein the Gilbert damping paramet…
Relativistic theory of magnetic inertia in ultrafast spin dynamics
Ritwik Mondal, Marco Berritta, Ashis K. Nandy +1
The influence of possible magnetic inertia effects has recently drawn attention in ultrafast magnetization dynamics and switching. Here we derive rigorously a description of inerti…
Signatures of relativistic spin-light coupling in ultrafast magneto-optical pump-probe experiments
Ritwik Mondal, Marco Berritta, Peter M. Oppeneer
Femtosecond magneto-optical pump-probe measurements of ultrafast demagnetization show an intriguing difference in the first 100 fs of the magneto-optical Kerr response depending on…
Relativistic theory of spin relaxation mechanisms in the Landau-Lifshitz-Gilbert equation of spin dynamics
Ritwik Mondal, Marco Berritta, Peter M. Oppeneer
Starting from the Dirac-Kohn-Sham equation we derive the relativistic equation of motion of spin angular momentum in a magnetic solid under an external electromagnetic field. This…
Magnetization switching of FePt nanoparticle recording medium by femtosecond laser pulses
R. John, M. Berritta, D. Hinzke +11
Manipulation of magnetization with ultrashort laser pulses is promising for information storage device applications. The dynamic of the magnetization response depends on the energy…
Ab Initio Theory of Coherent Laser-Induced Magnetization in Metals
Marco Berritta, Ritwik Mondal, Karel Carva +1
We present the first materials specific ab initio theory of the magnetization induced by circularly polarized laser light in metals. Our calculations are based on non-linear densit…
Ab initio investigation of light-induced relativistic spin-flip effects in magneto-optics
Ritwik Mondal, Marco Berritta, Karel Carva +1
Excitation of a metallic ferromagnet such as Ni with an intensive femtosecond laser pulse causes an ultrafast demagnetization within approximately 300 fs. It was proposed that the…