English
Related papers

Related papers: Optothermal nonlinearity of silica aerogel

200 papers

Infrared carbon stars without visible counterparts are generally known as extreme carbon stars. We have selected a subset of these stars with absorption features in the 10-13 $\mu$m range, which has been tentatively attributed to silicon…

Characterizing the nonlinear optical properties of various materials plays a prerequisite role in nonlinear optics. Among different methods, the well-known Z-scan technique and the modified versions have been recognized as a simple and…

Optics · Physics 2020-04-10 Xi Zeng , Pengfei Qi , Pin Chen , Lie Lin , Weiwei Liu

We analyze the resolved neutral hydrogen emission properties of a sample of eleven of the nearest spiral galaxies. Between 60 and 90% of the total HI line flux within the optical disk is due to a high brightness network (HBN) of emission…

Astrophysics · Physics 2009-10-30 Robert Braun

By means of the ultrafast optical Kerr effect method coupled to optical heterodyne detection (OHD-OKE), we characterize the third order nonlinear response of graphene at telecom wavelength, and compare it to experimental values obtained by…

CONTEXT: In the interpretation of stellar jet observations, the physical parameters are usually determined from emission line ratios, obtained from spectroscopic observations or using the information contained in narrow band images. The…

Astrophysics · Physics 2009-11-13 F. De Colle , C. del Burgo , A. C. Raga

For erbium-doped amorphous oxides, such as those that are used in compact lightwave devices interfaced with silicon, values of the refractive indices are commonly obtained empirically. This work, combining experimental and theoretical…

In order to point out the influence of thermal history (fictive temperature) and OH content on the elastic properties of silica glass, we have performed high resolution in situ Brillouin spectra of SiO2 glass from room temperature to the…

Materials Science · Physics 2007-05-23 R Le Parc , C Levelut , J Pelous , V. Martinez , B Champagnon

Photoabsorption cross sections of small sodium cluster cations (Na$_n^+$, n=3,5,7 and 9) were calculated at various temperatures with the time-dependent local-density-approximation (TDLDA) in conjunction with ab initio molecular dynamics…

Atomic and Molecular Clusters · Physics 2016-09-08 M. Moseler , H. Hakkinen , Uzi Landman

Two-dimensional (2D) metal halides have received more attention because of their electronic and optoelectronic properties. Recently, researchers are interested to investigate the thermoelectric properties of metal halide monolayers because…

Materials Science · Physics 2020-04-30 Atanu Betal , Jayanta Bera , Satyajit Sahu

Using the Effelsberg 100-m telescope, absorption in the (J,K) = (1,1), (2,2) and (3,3) inversion lines of ammonia (NH_3) was detected at a redshift of z = 0.6847 toward the gravitational lens system B0218+357. The lambda ~ 2cm absorption…

Astrophysics · Physics 2009-11-11 C. Henkel , N. Jethava , A. Kraus , K. M. Menten , C. L. Carilli , M. Grasshoff , D. Lubowich , M. J. Reid , .

In this work, nonlinear optical properties of Na: ZnO thin films (Na: ZnO) have been experimentally elaborated. The principal possibility to operate the nonlinear optical features using external laser beams is shown. The Na: ZnO films were…

We study the X-ray properties of LINER sources with definite detection of a broad H(alpha) emission line in their optical spectra, LINER 1s from Ho et al. sample. These objects preferentially harbor a low luminosity active nucleus at the…

Astrophysics of Galaxies · Physics 2015-05-28 G. Younes , D. Porquet , B. Sabra , J. N. Reeves

It may be possible to stabilize new superfluid phases of $^{3}$He with anisotropic silica aerogels. We discuss two methods that introduce anisotropy in the aerogel on length scales relevant to superfluid $^{3}$He. First, anisotropy can be…

Superconductivity · Physics 2009-11-11 J. Pollanen , S. Blinstein , H. Choi , J. P. Davis , T. M. Lippman , L. B. Lurio , W. P. Halperin

The transmission of light through low coverage regular and random arrays of glass supported silica micropillars of diameters 10 to 40 \micro\meter and height 10 \micro\meter is studied experimentally. Angle-resolved measurements of the…

A binary mixture of ferroelectric liquid crystals (FLCs) was used for the design of a channel waveguide. The FLCs possess two important functionalities: a chromophore with a high hyperpolarizability $\beta$ and photoreactive groups. The…

Soft Condensed Matter · Physics 2009-10-31 Valentina S. U. Fazio , S. T. Lagerwall , V. Zauls , S. Schrader , P. Busson , A. Hult , H. Motschmann

Nonlinear optical propagation in cholesteric liquid crystals (CLC) with a spatially periodic helical molecular structure is studied experimentally and modeled numerically. This periodic structure can be seen as a Bragg grating with a…

Photoluminescence (PL) and Raman spectra of sol-gel-derived silica glasses were studied in course of the consolidation of xerogel to dense glass. A number of ultraviolet PL bands in 3 eV - 4 eV region were found, which have not been…

We report on the performance of the statistical, X-ray absorption lines identification procedure XLINE-ID. As illustration, it is used to estimate the time averaged gas density $n_H(r)$ of a representative AGN's warm absorber ($T\approx…

Astrophysics of Galaxies · Physics 2016-08-08 J. M. Ramirez-Velasquez , J. Garcia

We report on thermodynamic and optical measurements of the condensation process of $^4$He in two silica aerogels of same porosity 95%, but different microstructures resulting from different pH during synthesis. For a base-catalyzed aerogel,…

Soft Condensed Matter · Physics 2007-05-23 Thierry Lambert , Florence Despetis , Laurent Puech , Pierre-Etienne Wolf

Nonlinear conductivity effects are studied experimentally and theoretically for thin samples of disordered ionic conductors. Following previous work in this field the {\it experimental nonlinear conductivity} of sodium ion conducting…

Materials Science · Physics 2009-11-11 Andreas Heuer , Sevi Murugavel , Bernhard Roling