Search results for "Interferometer"
showing 10 items of 109 documents
ALD thin ZnO layer as an active medium in a fiber-optic Fabry–Perot interferometer
2015
Abstract A novel optical fiber sensor of temperature using a thin ZnO layer fabricated by atomic layer deposition (ALD) is demonstrated for the first time. The thin ZnO layer was grown on the face of a standard optical telecommunication fiber SMF-28 and operates as a Fabry–Perot interferometer sensitive to temperature. The interferometer characterization was made in the temperature range extending from 50 to 300 °C with resolution equal to 1 °C. The output signal was analyzed by measurement of the shift of the maxima in spectral pattern. The sensitivity of temperature measurement is about 0.05 nm/°C. Furthermore, very good linearity of the sensor was achieved with correlation coefficient R2…
Class-B two-photon Fabry–Pérot laser
1998
Abstract We study the stationary operation and stability properties of a class-B two-photon Fabry–Perot laser. We show that, differently from the one-photon laser, the intensity emitted by the two-photon laser is larger in a Fabry–Perot than in a ring cavity. The lasing solution loses stability through a subcritical Hopf bifurcation, as it occurs in the unidirectional ring laser. The stability domain in the parameter space is larger in the Fabry–Perot than in the ring cavity configuration.
Arbitrary Phase Access for Stable Fiber Interferometers
2021
Well-controlled yet practical systems that give access to interference effects are critical for established and new functionalities in ultrafast signal processing, quantum photonics, optical coherence characterization, etc. Optical fiber systems constitute a central platform for such technologies. However, harnessing optical interference in a versatile and stable manner remains technologically costly and challenging. Here, degrees of freedom native to optical fibers, i.e., polarization and frequency, are used to demonstrate an easily deployable technique for the retrieval and stabilization of the relative phase in fiber interferometric systems. The scheme gives access (without intricate dev…
The 2009 Edition of the GEISA Spectroscopic Database
2011
The updated 2009 edition of the spectroscopic database GEISA (Gestion et Etude des Informations Spectroscopiques Atmosphériques; Management and Study of Atmospheric Spectroscopic Information) is described in this paper. GEISA is a computer-accessible system comprising three independent sub-databases devoted, respectively, to: line parameters, infrared and ultraviolet/visible absorption cross-sections, microphysical and optical properties of atmospheric aerosols. In this edition, 50 molecules are involved in the line parameters sub-database, including 111 isotopologues, for a total of 3,807,997 entries, in the spectral range from 10-6 to 35,877.031cm-1.The successful performances of the new …
Subwavelength sound screening by coupling space-coiled Fabry-Perot resonators
2017
We explore broadband and omnidirectional low frequency sound screening based on locally resonant acoustic metamaterials. We show that the coupling of different resonant modes supported by Fabry-Perot cavities can efficiently generate asymmetric lineshapes in the transmission spectrum, leading to a broadband sound opacity. The Fabry-Perot cavities are space-coiled in order to shift the resonant modes under the diffraction edge, which guaranty the opacity band for all incident angles. Indeed, the deep subwavelength feature of the cavities leads to avoid diffraction that have been proved to be the main limitation of omnidirectional capabilities of locally resonant perforated plates. We experim…
Plasmonic-assisted Mach-Zehnder Interferometric photonic sensor using aluminum waveguides
2020
We demonstrate a CMOS compatible interferometric plasmo-photonic sensor exploiting SisN4 photonic and aluminum (Al) plasmonic stripe waveguides. Experimental evaluation revealed bulk sensitivity of 4764 nm/RIU, holding promise for ultra-sensitive and low cost sensing devices.
Enhanced effects of variation of the fundamental constants in laser interferometers and application to dark matter detection
2015
We outline new laser interferometer measurements to search for variation of the electromagnetic fine-structure constant $\alpha$ and particle masses (including a non-zero photon mass). We propose a strontium optical lattice clock -- silicon single-crystal cavity interferometer as a novel small-scale platform for these new measurements. Multiple passages of a light beam inside an interferometer enhance the effects due to variation of the fundamental constants by the mean number of passages ($N_{\textrm{eff}} \sim 10^2$ for a large-scale gravitational-wave detector, such as LIGO, Virgo, GEO600 or TAMA300, while $N_{\textrm{eff}} \sim 10^5$ for a strontium clock -- silicon cavity interferomete…
Bidirectional Nonorthogonal Schardin-Lau Interferometer
1990
We discuss the formation of self-images of a 2-D grating composed by two rulings of equal period, but in-plane rotated. We describe the in-register condition for setting the lensless Lau effect, with this type of gratings; and we propose to use the above configuration for interferometrically visualizing, in noncoherent light, phase structures, in two nonorthogonal directions.
Design scheme for Mach–Zehnder interferometric coarse wavelength division multiplexing splitters and combiners
2006
I propose an analytical approach to design flattened wavelength splitters with cascaded Mach–Zehnder inter- ferometers when wavelength dependence of the directional couplers cannot be neglected. I start from a geo- metrical representation of the action of a doubly point-symmetrical filter, assuming no wavelength dependence of the couplers. Next I derive the analytical formulas behind its working principle and extend them to the wavelength-dependent case. I also show how the geometrical representation allows one to broaden the class of working structures. © 2006 Optical Society of America
Theoretical gain spectrum of coherently pumped mid-infrared Fabry-Pérot lasers
1992
Abstract We study the gain spectrum of a coherently pumped mid-infrared laser which operates in a linear-cavity (Fabry-Perot), using a three-level density matrix theory. Arbitrary pump and emission field strengths as well as pressure and Doppler broadening are considered. A new strong directional gain asymmetry is found, which is related to the presence of two counterpropagating components in the standing-wave generated field. Gain lineshapes in a wide range of operating conditions are obtained and analysed.