Related papers: Laser structuring for control of coupling between …
The shape of a few-cycle terahertz (THz) laser pulse can be optimized to provide control over conduction band populations in graphene. To demonstrate this control in a theoretical way, a spectral parametrization of the driving pulse using…
We consider the process of low-power light scattering by optical solitons in a slab waveguide with homogeneous and inhomogeneous refractive index core. We observe resonant reflection (Fano resonance) as well as resonant transmission of…
A laser pulse composed of a fundamental and an appropriately phased second harmonic can drive a time-dependent current of photoionized electrons that generates broadband THz radiation. Over the propagation distances relevant to many…
Conventional optical components shape the wavefront of propagating light by adjusting the optical path length, which requires the use of rather thick lenses, especially for the adjustment of terahertz (THz) radiation due to its long…
A laser pulse composed of a fundamental and properly phased second harmonic exhibits an asymmetric electric field that can drive a time-dependent current of photoionized electrons. The current produces an ultrashort burst of terahertz (THz)…
In this paper, a wideband and low-scattering metasurface in terahertz (THz) is introduced. The proposed coding metasurface is composed of four different graphene square patches in one layer, which has a distinct bias voltage. By optimizing…
We have investigated the formation of laser-induced periodic surface structures (LIPSS or ripples) on silicon upon excitation with p-polarized excimer laser pulses in the deep ultraviolet region (wavelength = 193 nm, pulse duration = 20…
This paper investigates the shape reconstructions of sub-wavelength objects from near-field measurements in transverse electromagnetic scattering. This geometric inverse problem is notoriously ill-posed and challenging. We develop a novel…
Semiconductor mode-locked lasers can be used in a variety of applications ranging from multi-carrier sources for WDM communication systems to time base references for metrology. Their packaging in compact chip- or module-level systems…
Irradiation of solid surfaces with high intensity, ultrashort laser pulses triggers a variety of secondary processes that can lead to the formation of transient and permanent structures over large range of length scales from mm down to the…
We report terahertz time-domain spectroscopy (TDTS) experiments demonstrating strong light-matter coupling in a terahertz (THz) LC-metamaterial in which the phonon resonance of a topological insulator (TI) thin film is coupled to the…
Terahertz (THz) radiation occupies a very large portion of the electromagnetic spectrum and has generated much recent interest due to its ability to penetrate deep into many organic materials without the damage associated with ionizing…
The efficiency of light coupling to surface plasmon polariton (SPP) represents a very important issue in plasmonics and laser fabrication of topographies in various solids. To illustrate the role of pre-patterrned surfaces and impact of…
A simple traveling wave antenna model is used to theoretically study emission from an array of filaments. Both transverse and longitudinal arrays of filaments are considered. The angular distribution and power in the THz signal are…
Many experiments in biological and medical sciences currently use multiphoton microscopy as a core imaging technique. To date, solid-state lasers are most commonly used as excitation beam sources. However, the most demanding applications…
We report on the morphological effects induced by the inhomogeneous absorption of radially polarized femtosecond laser irradiation of nickel (Ni) in sub-ablation conditions. A theoretical prediction of the morphology profile is performed…
A study of ripple formation on sapphire surfaces by 300-2000 eV Ar+ ion bombardment is presented. Surface characterization by in-situ synchrotron grazing incidence small angle x-ray scattering and ex-situ atomic force microscopy is…
We report about investigations of time-dependent structural modifications in single crystal graphene due to laser irradiation even at moderate power levels of 1mW in a diffraction limited spot. The structural modifications have been…
The aim of this work is to describe the behavior of a device capable to generate high frequency (~THz) acoustic phonons. This device consists in a GaAs-AlGaAs double barrier heterostructure that, when an external bias is applied, produces a…
Epitaxial graphene mesas and ribbons are investigated using terahertz (THz) nearfield microscopy to probe surface plasmon excitation and THz transmission properties on the sub-wavelength scale. The THz near-field images show variation of…