English
Related papers

Related papers: Minimum reflection channel in amplifying random me…

200 papers

While the absorption of light is ubiquitous in nature and in applications, the question remains how absorption modifies the transmission channels in random media. We present a numerical study on the effects of optical absorption on the…

Sensing and manipulating targets hidden under scattering media are universal problems that take place in applications ranging from deep-tissue optical imaging to laser surgery. A major issue in these applications is the shallow light…

Waves incident to a highly scattering medium are incapable of penetrating deep into the medium due to the diffusion process induced by multiple scattering. This poses a fundamental limitation to optically imaging, sensing, and manipulating…

While controlling particle diffusion in a confined geometry is a popular approach taken by both natural and artificial systems, it has not been widely adopted for controlling light transport in random media, where wave interference effects…

Optics · Physics 2016-01-06 Raktim Sarma , Alexey Yamilov , Seng Fatt Liew , Mikhael Guy , Hui Cao

A common strategy to compensate for losses in optical nanostructures is to add gain material in the system. By exploiting slow-light effects it is expected that the gain may be enhanced beyond its bulk value. Here we show that this route…

From the earth's crust to the human brain, remitted waves are used for sensing and imaging in a diverse range of diffusive media. Separating the source and detector increases the penetration depth of remitted light, yet rapidly decreases…

We report a detailed and systematic numerical study of wave propagation through a coherently amplifying random one-dimensional medium. The coherent amplification is modeled by introducing a uniform imaginary part in the site energies of the…

Disordered Systems and Neural Networks · Physics 2009-10-30 Sandeep K. Joshi , A. M. Jayannavar

Light propagating in an optical waveguide can gain or lose power through interaction with a travelling acoustic wave or radio-frequency modulation of permittivity. Here, we model this propagation by considering an optical wave interacting…

Optics · Physics 2026-02-03 M. Sumetsky

We present an analysis of enhanced wave transmission through random media with mirror symmetry about a reflecting barrier. The mathematical model is the acoustic wave equation and we consider two setups, where the wave propagation is along…

Mathematical Physics · Physics 2024-01-30 Liliana Borcea , Josselin Garnier

We examine quantum interference effects due to absorption and emission from multiple atoms coupled to a waveguide and highlight the modifications they entail in regards to single-photon transport properties. A prominent upshot of these…

Optics · Physics 2019-07-17 Debsuvra Mukhopadhyay , Girish S. Agarwal

Total internal reflection occurs for large angles of incidence, when light is incident from a high-refractive-index medium onto a low-index medium. We consider the situation where the low-index medium is active. By invoking causality in its…

Optics · Physics 2011-10-18 Jon Olav Grepstad , Johannes Skaar

The transmission matrix of a disordered medium, experimentally accessible for classical waves and central to the theory of mesoscopic electronic transport, supports transmission eigenchannels ranging from complete to vanishing transmission.…

Optics · Physics 2026-05-19 Israel Kurtz , Yiming Huang , Zhou Shi , Azriel Z Genack

We derive and validate a set of coupled Bloch wave equations for analyzing the reflection and transmission properties of active semiconductor photonic crystal waveguides. In such devices, slow-light propagation can be used to enhance the…

We consider a wave propagating through a thin disordered slab inside a wire or waveguide of finite width. In the dense weak scattering limit, the statistics for the complex reflection and transmission coefficients (the coherent field) is…

Optics · Physics 2014-10-23 Miztli Yépez , Saenz Juan Jose

We show that electron transport in a ballistic microchannel supporting both propagating and reflected modes can be completely blocked by applying a microwave electromagnetic field. The effect is due to resonant reflection caused by multiple…

Condensed Matter · Physics 2009-10-28 L. Y. Gorelik , M. Jonson , R. I. Shekhter

We demonstrate enhanced wave-like character of diffuse photon density waves (DPDW) in an amplifying random medium. The amplifying nature makes it contingent to choose the wave solution that grows inside the amplifying medium, and has a…

Introducing an axis of reflectional symmetry in a quasicrystal leads to the creation of localised edge modes that can be used to build waveguides. We develop theory that characterises reflection-induced localised modes in materials that are…

Mathematical Physics · Physics 2022-09-01 Bryn Davies , Richard V Craster

Following our recent theoretical and experimental results that show how zero-permittivity metamaterials may provide anomalous tunneling and energy squeezing through ultranarrow waveguide channels, here we report an experimental…

Materials Science · Physics 2009-11-13 Brian Edwards , Andrea Alu , Mario G. Silveirinha , Nader Engheta

The reflection and transmission amplitudes of waves in disordered multimode waveguides are studied by means of numerical simulations based on the invariant embedding equations. In particular, we analyze the influence of surface-type…

Disordered Systems and Neural Networks · Physics 2009-10-31 J. A. Sanchez-Gil , V. Freilikher , A. A. Maradudin , I. Yurkevich

Introduction of optical gain to a disordered system results in enhanced fluctuations [$F_{(2)}=var(\tilde{g})/< \tilde{g} >^2$] of dimensionless conductance $\tilde{g}$, similar to the effect of Anderson localization in passive medium.…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Alexey Yamilov , Hui Cao
‹ Prev 1 2 3 10 Next ›