English
Related papers

Related papers: Spectral Singularities and a New Method of Generat…

200 papers

High harmonic generation (HHG) from semiconductors and insulators has become a very active area of research due to its great potential for developing compact HHG devices. Here we show that by growing monolayers (ML) of insulators on…

Atomic Physics · Physics 2016-12-28 Néstor F. Aguirre , Fernando Martín

Conventional lasers make use of optical cavities to provide feedback to gain media. Conversely, mirrorless lasers can be built by using disordered structures to induce multiple scattering, which increases the effective path length in the…

Atomic Physics · Physics 2015-06-12 Quentin Baudouin , Nicolas Mercadier , Vera Guarrera , William Guerin , Robin Kaiser

We have fabricated a layered nano-composite by alternating metal and gain medium layers, the gain dielectric consisting of a polymer incorporating optically pumped dye molecules. Exploiting an improved version of the effective medium…

Optics · Physics 2015-05-28 Carlo Rizza , Andrea Di Falco , Alessandro Ciattoni

We propose a new method for determination of element abundances in stellar atmospheres aimed for the automatic processing of high-quality stellar spectra. The pan-spectral method is based on weighted cumulative line-widths Q of studied…

Astrophysics · Physics 2012-04-02 A. Sapar , A. Aret , L. Sapar , R. Poolamäe

Wavelength widely tunable infrared fiber lasers that simultaneously deliver high pulse energies with narrow linewidths are critical for applications ranging from spectroscopy to nonlinear optics, yet achieving this combination has remained…

Non-Hermitian systems characterized by suitable spatial distributions of gain and loss can exhibit "spectral singularities" in the form of zero-width resonances associated to real-frequency poles in the scattering operator. Here, we study…

Optics · Physics 2020-04-22 Massimo Moccia , Giuseppe Castaldi , Andrea Alù , Vincenzo Galdi

In a laser, the control of its spectral emission depends on the physical dimensions of the optical resonator, limiting it to a set of discrete cavity modes at specific frequencies. Here, we overcome this fundamental limit by demonstrating a…

In this Letter, we theoretically propose for the first time that graphene monolayers can be used for superscatterer designs. We show that the scattering cross section of the bare deep-subwavelength dielectric cylinder is markedly enhanced…

Optics · Physics 2015-06-01 R. J. Li , X. Lin , S. S. Lin , X. Liu , H. S. Chen

Recently it has been proposed that a planar slab of material, for which both the permittivity and permeability have the values of -1, could bring not only the propagating fields associated with a source to a focus, but could also refocus…

Condensed Matter · Physics 2009-11-07 D. R. Smith , D. Schurig , Marshall Rosenbluth , S. Schultz , S. Anantha Ramakrishna , J. B. Pendry

We demonstrate a novel approach to obtain resonance linewidth below that limited by coherence lifetime. Cross correlation between induced intensity modulation of two lasers coupling the target resonance exhibits a narrow spectrum. 1/30 of…

Atomic Physics · Physics 2012-12-07 Feng Lei , Pengxiong Li , Liang Jiang , Jianming Wen , Yanhong Xiao

We describe a new method for measuring galaxy magnification due to weak gravitational lensing. Our method makes use of a tight scaling relation between galaxy properties that are modified by gravitational lensing, such as apparent size, and…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-07 Eric M. Huff , Genevieve J. Graves

We study spectral singularities and their application in determining the threshold gain coefficient $g^{(E/M)}$ for oblique transverse electric/magnetic (TE/TM) modes of an infinite planar slab of homogenous optically active material. We…

Quantum Physics · Physics 2015-06-23 Ali Mostafazadeh , Mustafa Sarisaman

Hyperuniform structures possess the ability to confine and drive light, although their fabrication is extremely challenging. Here we demonstrate that speckle patters obtained by a superposition of randomly arranged sources of Bessel beams…

To effectively apply passive speckle reduction methods, it is essential to use an illumination system that maximally exploits the non-ideal temporal coherence and angular diversity (spatial coherence reduction) of laser light. This study…

Optics · Physics 2025-04-28 A. Lapchuk , O. Prygun , D. Manko , I. Gorbov , Y. Morozov

The electromagnetic response of subwavelength wires coated with a graphene monolayer illuminated by a linearly polarized plane waves is investigated. The results show that the scattering and extintion cross-sections of the coated wire can…

Optics · Physics 2015-05-13 Máximo Riso , Mauro Cuevas , Ricardo A. Depine

We discuss a class of lasing modes created by a spatially inhomogeneous gain profile. These lasing modes are "extra modes", in addition to, and very different from, conventional lasing modes, which arise from the passive cavity resonances.…

Optics · Physics 2015-05-28 Li Ge , Y. D. Chong , S. Rotter , H. E. Türeci , A. D. Stone

We report a versatile and cost-effective way of controlling the unsaturated loss, modulation depth and saturation fluence of graphene-based saturable absorbers (GSAs), by changing the thickness of a spacer between SLG and a high-reflection…

The notion that Stimulated Brillouin Scattering (SBS) is primarily defined by bulk material properties has been overturned by recent work on nanoscale waveguides. It is now understood that boundary forces of radiation pressure and…

Optics · Physics 2015-10-21 Nathan Dostart , Seunghwi Kim , Gaurav Bahl

Theoretical studies of superradiant lasing on optical clock transitions predict a superb frequency accuracy and precision closely tied to the bare atomic linewidth. Such a superradiant laser is also robust against cavity fluctuations when…

Quantum Physics · Physics 2021-11-02 Anna Bychek , Christoph Hotter , David Plankensteiner , Helmut Ritsch

The concept of spaser, as the coherent near-field generator, based on nanometric plasmonic resonators, has been successfully demonstrated in number of experiments. Here we have developed the theoretical framework for description of the…

Optics · Physics 2014-05-21 Pavel Ginzburg , Anatoly V. Zayats