Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 2609.31203

Orbital photoinduced Faraday effect in a lattice of conducting disks

A. A. Gunyaga·M. V. Durnev
View original source ↗Read source document ↗Export metadata ↓

Abstract

We present a theoretical study of pump-induced Faraday and Kerr rotation in a two-dimensional lattice of conducting disks. We propose a mechanism of Faraday and Kerr responses in which a circularly polarized pump directly induces a high-frequency Hall component $σ_{xy}=-σ_{yx}$ of the electron conductivity tensor at the probe frequency. Microscopically, $σ_{xy}$ originates from the third-order nonlinear response of the electron gas rather than from the real magnetic field created by solenoidal charge currents in the inverse Faraday effect. We show that the Faraday and Kerr rotation angles are significantly enhanced when the pump and probe frequencies are tuned close to the plasmon resonance of the disks, reaching $\sim 0.1^\circ$ per 1~kW/cm$^2$ of incident pump intensity in the terahertz range. This mechanism can explain recently observed giant pump-induced Faraday rotation in graphene disk lattices.

Explore related subjects

cond-mat.mes-hall

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A. A. Gunyaga, M. V. Durnev. 2026-09-25. Orbital photoinduced Faraday effect in a lattice of conducting disks. https://arxiv.org/abs/2609.31203

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

KEEP EXPLORING

Related papers

arXiv2026

Intertwined bulk photocarrier and interfacial barrier dynamics in van der Waals point-contact Schottky junctions

Schottky junctions based on transition-metal dichalcogenides underpin next-generation optoelectronic devices, yet the nanoscale carrier dynamics that ultimately govern their performance remain largely inaccessible. Here, we employ optical pump-probe time-resolved atomic force microscopy (OPP-TR-AFM) to investigate the spatiotemporal response of a WSe$_2$/PtIr van der Waals Schottky junction. Under backside illumination, photocarriers generated in bulk WSe$_2$ produce a local junction response through coupled bulk carrier transport and interfacial barrier modulation. We show that the time-resolved current is consistently explained by the competition between long-lived hole diffusion governed by the occupancy of bulk trap states and thermionic emission current modulated by the surface photovoltage. This mechanism is supported by transient absorption spectroscopy, light-modulated current-voltage measurements, and numerical simulations. Furthermore, spatial mapping reveals pronounced nanoscale variations in the coupled dynamics of carrier transport and interfacial barrier modulation. These results demonstrate that OPP-TR-AFM provides a new framework for resolving the coupled behavior of bulk carriers and interfacial barrier dynamics in van der Waals Schottky junctions with simultaneous spatial and temporal resolution, establishing it as a powerful approach for investigating the microscopic processes that play a crucial role in the development of next-generation optoelectronic devices.

cond-mat.mes-hall↗
arXiv2026

Thermal conductivity tuning of scalable nanopatterned silicon membranes measured with a three-probe method

Phononic silicon structures have emerged as an integrable and scalable nanosystem for tailoring thermal transport. However, their widespread adoption has been limited by their complex fabrication pathways. Alongside, the reliable characterization of thermal properties in suspended nanostructured films remains challenging, as thermal contact resistances often hinder the accuracy of measurements. In this work, we demonstrate a clear and controllable reduction of thermal conductivity in nanopatterned silicon membranes. A block copolymer self-assembly approach is employed to fabricate nanoholed silicon films with a pitch of 63 nm and hole diameters of 35 nm. Additionally, we introduce an extension of the three-probe technique that enables robust, quantitative, and spatially resolved thermal conductivity measurements in complex thin-film systems, accounting for thermal contact artifacts. The method is validated through measurements on unpatterned 40 nm-thick silicon thin films between 30 and 350 K, yielding a room-temperature thermal conductivity of 46.5 W/m.K. Finally, we further show that controlled etching of the nanoholes provides a powerful means to tune thermal transport in the overall studied temperature range, establishing hole etch depth control as an effective parameter in phononic silicon. Specifically, a fivefold reduction in thermal conductivity is achieved, reaching 7.3 W/m.K for fully etched-through membranes at room temperature.

cond-mat.mes-hall↗
arXiv2026

Magnetoconductivity of two-dimensional Dirac cones and gapped nodal-rings under impurity-potentials in the ultraquantum limit

We investigate the dc magnetoconductivity of two-dimensional Dirac cones and gapped nodal rings (GNRs) subjected to a perpendicular magnetic field, which quantises the electronic spectrum into Landau levels (LLs). Working in the ultraquantum limit, where only the lowest LL (LLL) is partially occupied, we employ the Kubo--Bastin formalism to compute the transport coefficients for pointlike, Gaussian, and Yukawa impurity-potentials. For the Dirac case, the longitudinal conductivity is field-independent for pointlike impurities and a monotonic function of $B$ for the Gaussian and Yukawa potentials, while the Hall conductivity vanishes identically owing to the particle-hole symmetry of the two neighbouring LLs. The GNR case is qualitatively different: its non-monotonic stretched-checkmark LL spectrum causes the effective LLL to migrate to successively lower indices as the field increases, producing a pronounced oscillatory structure in both conductivities. The longitudinal response develops resonant peaks at LLL degeneracies, while the Hall conductivity traces out a sawtooth pattern with sharp zero-crossings at these same points. These results establish distinct transport fingerprints for the two systems in the extreme quantum limit, and provide a theoretical framework for interpreting magnetotransport experiments on GNRs.

cond-mat.mes-hall↗