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Concept

Coefficients d'Einstein

Publications associées (15)

Upper bounds on technoemission rates from 60 years of "silence"

Claudio Grimaldi

The lack of detection to date of electromagnetic technosignatures implies either that we have been unable to detect them due to incomplete sampling of the search space or that we cannot detect them because the Earth has been located during the entire histo ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Ultrafast tunable lasers using lithium niobate integrated photonics

Tobias Kippenberg, Junqiu Liu, Rui Ning Wang, Johann Emmeram Riemensberger, Anat Siddharth, Guanhao Huang, Mikhail Churaev, Viacheslav Snigirev

Early works(1) and recent advances in thin-film lithium niobate (LiNbO3) on insulator have enabled low-loss photonic integrated circuits(2,3), modulators with improved half-wave voltage(4,5), electro-optic frequency combs(6) and on-chip electro-optic devic ...

NATURE PORTFOLIO2023

Low-noise frequency-agile photonic integrated lasers for coherent ranging

Tobias Kippenberg, Junqiu Liu, Rui Ning Wang, Johann Emmeram Riemensberger, Wenle Weng, Jijun He, Anat Siddharth, Andrey Voloshin, Viacheslav Snigirev, Vladimir Shadymov

Stable and tunable integrated lasers are fundamental building blocks for applications from spectroscopy to imaging and communication. Here the authors present a narrow linewidth hybrid photonic integrated laser with low frequency noise and fast linear wave ...

Nature Portfolio2022

Demography of galactic technosignatures

Claudio Grimaldi

Probabilistic arguments about the existence of technological life beyond Earth traditionally refer to the Drake equation to draw possible estimates of the number of technologically advanced civilizations releasing, either intentionally or not, electromagne ...

OXFORD UNIV PRESS2021

n-photon blockade with an n-photon parametric drive

Fabrizio Minganti

We propose a mechanism to engineer an n-photon blockade in a nonlinear cavity with an n-photon parametric drive lambda(adagger n + an). When an n-photon-excitation resonance condition is satisfied, the presence of n photons in the cavity suppress ...

AMER PHYSICAL SOC2021

Orientation Dependence of Plasmonically Enhanced Spontaneous Emission

Olivier Martin

We computationally explore how the orientation of dipolar emitters placed near plasmonic nanostructures affects their radiative enhancement and spontaneous emission rate. We demonstrate that the expressions for these quantities show a subtle dependence on ...

American Chemical Society2016

Surface-Plasmon-Induced Modification on the Spontaneous Emission Spectrum via Subwavelength-Confined Anisotropic Purcell Factor

Olivier Martin

The mechanism of using the anisotropic Purcell factor to control the spontaneous emission linewidths in a four-level atom is theoretically demonstrated; if the polarization angle bisector of the two dipole moments lies along the axis of large/small Purcell ...

American Chemical Society (ACS)2012

Resonances and absorption enhancement in thin film silicon solar cells with periodic interface texture

Christophe Ballif, Franz-Josef Haug, Karin Söderström, Ali Naqavi

We study absorption enhancement by light scattering at periodically textured interfaces in thin film silicon solar cells. We show that the periodicity establishes resonant coupling to propagating waveguide modes. Ideally, such modes propagate in the high i ...

American Institute of Physics2011

Bias-dependent absorption coefficient of the absorber section in GaN-based multisection laser diodes

Nicolas Grandjean, Jean-François Carlin, Antonino Francesco Castiglia, Luca Alex Milo Sulmoni

We measure the modal absorption coefficient of the InGaN quantum wells (QWs) in the absorber section of (Al,In)GaN multisection laser diodes as a function of bias voltage and photon energy using optical gain-spectroscopy. In the examined laser diodes, the ...

AIP American Institute of Physics2010

Full-wave analysis of photonic-crystal structures with multi quantum well active region

Banafsheh Abasahl

In this paper, a semi-classical formulation for modeling photonic-crystal (PC) structures with a four-layer multi quantum well (MQW) active region is presented. The formulation treats the electromagnetic fields as a classical entity, while employing the qu ...

2010

Cavity-enhanced photonic crystal light-emitting diode at 1300 nm

Laurent Balet, Blandine Alloing

We report direct evidence of enhanced spontaneous emission in a photonic crystal light-emitting diode (LED) at telecom wavelength (lambda similar to 1300 nm). This result is crucial to obtain an electrically driven single photon source with high extraction ...

2009

Enhanced spontaneous emission in a photonic-crystal light-emitting diode

Laurent Balet, Blandine Alloing

We report direct evidence of enhanced spontaneous emission in a photonic-crystal (PhC) light-emitting diode. The device consists of p-i-n heterojunction embedded in a suspended membrane, comprising a layer of self-assembled quantum dots. Current is injecte ...

American Institute of Physics2008

Numerical parametric lens for shifting, magnification and complete aberration compensation in digital holographic microscopy

Pierre Marquet, Christian Depeursinge, Jonas Kühn, Tristan Colomb, Etienne Cuche, Florian Charrière, Nicolas Aspert, Frédéric Montfort, Stéphane Bourquin, Mihaela Marian

The concept of numerical parametric lenses (NPL) is introduced to achieve wavefront reconstruction in digital holography. It is shown that operations usually performed by optical components and described in ray geometrical optics, such as image shifting, m ...

2006

Lattice-matched distributed Bragg reflectors for nitride-based vertical cavity surface emitting lasers

Nicolas Grandjean, Jean-François Carlin, Marc Ilegems, Eric Feltin, Raphaël Butté, Julien Dorsaz

Very narrow spontaneous emission (Deltalambda similar to 0.5 nm), corresponding to a quality factor Q in excess of 800, has been obtained under continuous-wave excitation at room temperature with an AlInN/GaN monolithic microcavity. The structure is made o ...

2005

On isotopically selective collisional energy transfer and infrared multiple photon absorption by vibrationally highly excited molecules

Richard Bossart

This study focuses on an interesting and important phenomenon that was employed in a new approach to laser isotope separation that has been recently proposed and developed in our laboratory for highly selective separation of carbon isotopes. This approach ...

EPFL2005