English
Related papers

Related papers: Terahertz Nonlinear Index Extraction via Full-Phas…

200 papers

A model is described that relates the temperature coefficient of the optical absorption spectrum of pure water to the frequency derivative of that spectrum and two parameters that quantify the dependence of a peak's amplitude and its…

Materials Science · Physics 2015-06-12 J. B. Cumming

We employ a silicon dielectric waveguide to confine and concentrate terahertz pulses, and observe that the absorption saturates under strong terahertz fields. By comparing the response between lightly-doped and intrinsic silicon waveguides,…

Materials Science · Physics 2015-03-20 Shanshan Li , Gagan Kumar , Thomas E. Murphy

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…

Accurate knowledge of absorption coefficient of a sample is a prerequisite for measuring the third order optical nonlinearity of materials, which can be a serious limitation for unknown samples. We introduce a method, which measures both…

Optics · Physics 2007-05-23 A. Sharan , S. Abbas Hosseini , D. Goswami

We report the first terahertz Kerr measurements on bulk crystals of the topological insulator Bi2Se3. At T=10K and fields up to 8T, the real and imaginary Kerr angle and reflectance measurements utilizing both linearly and circularly…

Strongly Correlated Electrons · Physics 2010-09-29 G. S. Jenkins , A. B. Sushkov , D. C. Schmadel , N. P. Butch , P. Syers , J. Paglione , H. D. Drew

Although diamond photonics has driven considerable interest and useful applications, as shown in frequency generation devices and single photon emitters, fundamental studies on the third-order optical nonlinearities of diamond are still…

Inspired by the capability of structured illumination microscopy in subwavelength imaging, many researchers devoted themselves to investigating this methodology. However, due to the free propagating feature of the traditional structured…

The nonlinear polaronic response of electrons solvated in liquid 2-propanol is studied by two-dimensional terahertz spectroscopy. Solvated electrons with a concentration of c$_e \approx$ 800 $\mu$M are generated by femtosecond…

Chemical Physics · Physics 2023-10-05 Matthias Runge , Klaus Reimann , Michael Woerner , Thomas Elsaesser

The parametric formulas are obtained whereby the refractive index and the light group velocity could be calculated for any water state (salinity, pressure, temperature) inside of the light wavelength region from 200 nm to 1200 nm. These…

Instrumentation and Detectors · Physics 2007-05-23 I. A. Danilchenko

The axial dependence of femtosecond filamentation in air is measured under conditions of varying laser pulsewidth, energy, and focusing f-number. Filaments are characterized by the ultrafast z-dependent absorption of energy from the laser…

We present the theory, design, and realization of a polarization-insensitive metamaterial absorber for terahertz frequencies. We derive geometrical-independent conditions for effective medium absorbers in general, and for resonant…

Materials Science · Physics 2009-11-13 N. I. Landy , C. M. Bingham , T. Tyler , N. Jokerst , D. R. Smith , W. J. Padilla

We have conducted a study combining H2O lines in two spectral regions. First, Infrared Space Observatory observations of several H2O thermal lines seen in absorption toward Sgr B2(M) at a spectral resolution of 35 kms^-1 have been analyzed.…

Astrophysics · Physics 2009-11-11 J. Cernicharo , J. R. Goicoechea , J. R. Pardo , A. Asensio Ramos

General analytic expressions for the total absorption coefficient of strong electromagnetic waves caused by confined electrons in Infinite semi-parabolic plus Semi-inverse Squared Quantum Wells (ISPSISQW) are obtained by using the quantum…

Mesoscale and Nanoscale Physics · Physics 2024-12-25 Cao Thi Vi Ba , Nguyen Quang Bau , Anh-Tuan Tran , Tang Thi Dien

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

Terahertz radiation generation from liquid water has long been considered to be impossible due to strong absorption. A few very recent works reported terahertz generation from water, but the mechanism is not clear and the efficiency demands…

Plasma Physics · Physics 2019-07-10 L. -L. Zhang , W. -M. Wang , T. Wu , S. -J. Feng , K. Kang , C. -L. Zhang , Y. Zhang , Y. -T. Li , Z. -M. Sheng , X. -C. Zhang

Total absorption, defined as the net flux of energy out of a bounded region averaged over one cycle for time harmonic motion, must be non-negative when there are no sources of energy within the region. This passivity condition places…

Classical Physics · Physics 2017-04-05 Andrew N. Norris

Together with the 74 lines belonging to (0,9,0)-(0,0,0) band, the high-resolution absorption spectrum of H2O+ was observed in the visible region of 16680 -17300 (cm-1) using optical heterodyne magnetic rotation enhanced velocity modulation…

Optics · Physics 2007-05-23 Hua Zhuang , Yangqin Chen , Wenhai Ji , Shenghai Wu , Zhiyi Bi , Longsheng Ma

X-ray Raman spectra of liquid, sub- and super- critical water at the oxygen K-edge were measured, at densities 1.02 - 0.16 gcm^-3. Measurements were made along both an isotherm and an isochore passing near the critical point. As density is…

Chemical Physics · Physics 2012-10-17 D. Ishikawa , Y. Q. Cai , D. M. Shaw , J. S. Tse , N. Hiraoka , A. Q. R. Baron

One source of disturbance in a pulsed T-ray signal is attributed to ambient water vapor. Water molecules in the gas phase selectively absorb T-rays at discrete frequencies corresponding to their molecular rotational transitions. This…

Computational Engineering, Finance, and Science · Computer Science 2008-07-16 Withawat Withayachumnankul , Bernd M. Fischer , Samuel P. Mickan , Derek Abbott