Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · cond-mat/0402475

Interface-Localized Mode In Bilayer Film Ferromagnetic Resonance Spectrum

H. Puszkarski·S. Mamica
View original source ↗Read source document ↗Export metadata ↓

Abstract

Ferromagnetic resonance (FMR) in exchange-coupled bilayer films has been the subject of intensive studies in recent years. From the experimental viewpoint, a characteristic feature of this FMR is that some specimens show single resonance, whereas others show double resonance. Moreover, double resonance can exhibit a regular pattern, in which the high-field (HF) line intensity surpasses that of the low-field (LF) line, or it can exhibit an inverted pattern with the HF line less intense than the LF line. There is a general belief that the inverted FMR pattern occurs when the HF line is an "optic mode", i.e. an out-of-phase composition of individual sublayer modes, and the LF line is an "acoustic mode", or an in-phase mode composition. The existing theoretical explanations of bilayer ferromagnetic resonance are, as a rule, based on phenomenological equation of motion of the magnetization vector. In this paper, we propose a theory of FMR in ultrathin bilayers based on an entirely microscopic approach, using the Heisenberg model of localized spins and assuming that the two ferromagnetic sublayers are exchange-coupled through their interface. This rigorous microscopic FMR theory does explain the inverted pattern of the bilayer FMR spectrum by assuming the HF line to correspond to an in-phase mode, but of interface-localized nature; this gives a possibility to explore the HF resonance line corresponding to the interface-localized mode as a potential source of information concerning the bilayer interface.

Explore related subjects

cond-mat.other

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

H. Puszkarski, S. Mamica. 2004-02-18. Interface-Localized Mode In Bilayer Film Ferromagnetic Resonance Spectrum. https://arxiv.org/abs/cond-mat/0402475

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Microscopic Understanding of Thermal-magnon Transport in a Low-damping Ferrimagnetic Thin Films

Thermally generated magnons enable heat-driven spin transport in magnetic insulators, yet the microscopic mechanisms governing their propagation remain poorly understood. Here, we investigate thermal magnon transport in low-damping Li$_{0.5}$Al$_{1.0}$Fe$_{1.5}$O$_4$/Pt nanodevices using a nonlocal spin Seebeck geometry that separates magnon transport from local thermoelectric effects. Thermal imaging establishes a detector region outside the thermal healing length, enabling intrinsic nonlocal measurements. We find that thermal magnon transport is strongly suppressed by magnetic fields far above saturation. Brillouin light scattering reveals that increasing field reduces the group velocity of backward volume magnons, providing a microscopic origin for the observed reduction in magnon spin diffusion length. We further find that thermal magnon transport decreases with increasing temperature despite an increasing magnon population. Micromagnetic simulations reproduce this behavior only when a temperature-dependent exchange stiffness is included. These results identify magnon group velocity and exchange stiffness as key parameters governing thermal magnon transport in ferrimagnetic thin films.

cond-mat.other↗
arXiv2026

Transport properties and topological phase transitions for a Creutz-Su-Schrieffer-Heeger ladder

In this work, we investigate the electronic, topological, and transport properties of a Creutz-Su-Schrieffer-Heeger (CSSH) ladder. Using a tight-binding model within the Green's function formalism, we calculate the energy spectrum, local density of states (LDOS), and electronic transmission. We first determine the energy spectrum of the CSSH ladder and analyze the different topological phases present in the system, identifying one trivial phase and three distinct nontrivial regions. We then study electronic transport and show that the transmission reproduces the different topological phases through characteristic transport signatures. Finally, we derive the conditions for the emergence of non-topological flat bands and demonstrate that these bands also provide the necessary conditions for the formation of bound states in the continuum (BICs). Our results establish a direct connection between the topological properties, flat-band formation, and electronic transport in the CSSH ladder.

cond-mat.other↗
arXiv2026

Exact Phase-Space Rotation in the Trapped Quantum Calogero Model

We develop a microscopic phase-space description of the quantum Calogero model in the presence of an external harmonic confining potential. Building on the quantum Lax-pair structure, we construct a Hermitian Wigner operator whose expectation value obeys the exact phase-space evolution equation d_t rho + lambda d_x rho - Omega^2 x d_lambda rho = 0 for arbitrary initial states and to all orders in the interaction strength. The resulting dynamics is a rigid rotation in phase space with period 2 pi/Omega, providing a microscopic realization of the isochronous dynamics of the trapped Calogero model. We further show that the moments of the phase-space density form rotating multiplets rather than independent conserved quantities. In particular, within the quadratic sector, the unique conserved combination is proportional to the trapped Hamiltonian, providing a nontrivial consistency check of the construction. In the limit Omega -> 0, the equation reduces to the exact free-streaming equation of the untrapped model.

cond-mat.other↗