A5039443297- Spectroscopy and Laser Applications
- Semiconductor Lasers and Optical Devices
- Photonic and Optical Devices
- Semiconductor Quantum Structures and Devices
- Atmospheric Ozone and Climate
- Laser Design and Applications
- Terahertz technology and applications
- Strong Light-Matter Interactions
- Advanced Fiber Laser Technologies
- Plasmonic and Surface Plasmon Research
- Quantum and electron transport phenomena
- Atmospheric and Environmental Gas Dynamics
- Mechanical and Optical Resonators
- Thermal Radiation and Cooling Technologies
- Quantum optics and atomic interactions
- Quantum Information and Cryptography
- Photonic Crystals and Applications
- Optical properties and cooling technologies in crystalline materials
- Air Quality Monitoring and Forecasting
- Advanced Semiconductor Detectors and Materials
- Optical Wireless Communication Technologies
- Metamaterials and Metasurfaces Applications
- Gold and Silver Nanoparticles Synthesis and Applications
- Spectroscopy and Quantum Chemical Studies
- Laser-Matter Interactions and Applications
École Normale Supérieure - PSL
2010-2025
Centre National de la Recherche Scientifique
2015-2024
Université Paris Cité
2015-2024
Nanyang Technological University
2018-2024
Sorbonne Université
2010-2024
Université Paris Sciences et Lettres
2019-2024
Sorbonne Paris Cité
2013-2024
Laboratoire de Physique de l'ENS
2019-2024
École Normale Supérieure
2019-2024
Zhejiang University
2024
A semiconductor injection laser that differs in a fundamental way from diode lasers has been demonstrated. It is built out of quantum structures were grown by molecular beam epitaxy and designed band structure engineering. Electrons streaming down potential staircase sequentially emit photons at the steps. The steps consist coupled wells which population inversion between discrete conduction excited states achieved control tunneling. strong narrowing emission spectrum, above threshold,...
A unipolar injection quantum cascade (QC) laser grown in an AlGaAs/GaAs material system by molecular beam epitaxy, is reported. The active a 30 period sequence of injectors/active regions made from Al0.33Ga0.67As/GaAs-coupled wells. For this device special waveguide design, which complies with GaAs heavily doped substrate and very short Al0.90Ga0.10As cladding layers, has been optimized. At heat-sink temperature 77 K, the emission wavelength 9.4 μm peak optical power exceeding 70 mW...
The regime of ultrastrong light-matter interaction has been investigated theoretically and experimentally, using zero-dimensional electromagnetic resonators coupled with an electronic transition between two confined states a semiconductor quantum well. We have measured splitting the modes that amounts to 48% energy transition, highest ratio ever observed in system. Our analysis, based on microscopic theory, shows nonlinear polariton splitting, signature this regime, is dynamical effect...
The high power operation of mid-infrared quantum cascade lasers at temperatures up to T=320 K is reported. Gain temperature optimized by a design combining low doping, funnel injector, and three-well vertical transition active region. A molecular beam epitaxy grown InP top cladding layer also used optimize heat dissipation. peak pulsed optical 200 mW an average 6 are obtained 300 wavelength λ=5.2 μm. devices operate in continuous wave 140 K.
Pulsed single mode operation of distributed feedback quantum cascade lasers is reported above room temperature at both 5.4 and 8 μm wavelengths. Peak optical powers up to 60 mW 300 K are obtained with a tuning range ∼60 nm from 100 ∼320 K. The linewidth limited by thermal drift during the pulse typical value 0.3 cm−1 for 10 ns long
The phenomenon of electromagnetically induced quantum coherence is demonstrated between three confined electron subband levels in a well which are almost equally spaced energy. Applying strong coupling field, two-photon resonant with the 1-3 intersubband transition, produces pronounced narrow transparency feature 1-2 absorption line. This result can be understood terms all states being simultaneously driven into ``phase-locked'' by single field. We describe effect theoretically density...
A sum rule for electronic intersubband transitions has been derived following Kane's model, beyond the quadratic dispersion relations. The takes into account effects of nonparabolicity and different effective masses in well barrier materials; it depends on property ground state system and, as such, shape potential. boundaries validity matrix element computations are also discussed case where only conduction band is included. Experimental results presented bound-to-bound bound-to-continuum...
Experimental evidence that in quantum cascade lasers electron injection into the active region is controlled by resonant tunneling between two-dimensional subbands discussed. A quantitative analysis carried out using an equation for current density based on a tight-binding approximation. Electron optimized when limited lifetime of excited state laser transition. In this regime, quasi-equilibrium reached population injector ground and transition characterized common quasi-Fermi level. The...
The room-temperature (300 K), pulsed mode operation of a GaAs-based quantum-cascade laser is presented. This has been achieved by the use GaAs/Al0.45Ga0.55As heterostructure which offers maximum Γ–Γ band offset (390 meV) for this material system without inducing presence indirect barrier states. Thus, better electron confinement achieved, countering loss injection efficiency with temperature. These devices show ∼100 K increase in operating temperature respect to equivalent designs using an...
A new midinfrared (λ∼4.5 μm) intersubband quantum cascade laser based on a vertical transition is reported. superlattice graded gap region was incorporated in the design to provide strong electron confinement upper state using Bragg reflector. Pulsed operation at 100 K reported with threshold current density of Jth=3 kA/cm2 and measured slope efficiency 300 mW/A.
A new coupled-quantum-well semiconductor with triply resonant third-order nonlinear susceptibility ${\mathrm{\ensuremath{\chi}}}_{3\mathrm{\ensuremath{\omega}}}^{(3)}$ has been designed and demonstrated using AlInAs/GaInAs heterostructures grown by molecular-beam epitaxy. In order to maximize \ensuremath{\Vert}${\mathrm{\ensuremath{\chi}}}_{3\mathrm{\ensuremath{\omega}}}^{(3)}$\ensuremath{\Vert} our structure tailored in such a way the product of dipole matrix elements relevant intersubband...
We have demonstrated that a metal-dielectric-metal microcavity combined with quantum well intersubband transitions is an ideal system for the generation of cavity polariton states in terahertz region. The metallic has highly confined radiation modes can be tuned resonance transition. In this we were able to measure very strong light-matter splitting (the Rabi 2 variant Planck's over 2pi Omega R), corresponding 22% transition energy. believe result first demonstration polaritons frequency range.
Coupled quantum wells present unique opportunities for engineering new semiconductors with large optical nonlinearities associated intersubband transitions in the infrared. In this paper we report an depth study of these properties AlInAs/GaInAs heterostructure material system grown by molecular beam epitaxy. We show that judicious control tunnel coupling between and thickness latter one can design wavefunctions energy levels such a may structures behave as quasi-molecules extremely dipole...
We present an experimental and theoretical study of the optical properties metal-dielectric-metal structures with patterned top metallic surfaces, in THz frequency range. When thickness dielectric slab is very small respect to wavelength, these are able support strongly localized electromagnetic modes, concentrated subwavelength metal-metal regions. provide a detailed analysis physical mechanisms which give rise photonic modes. Furthermore, our model quantitatively predicts resonance...
We provide a theoretical description of the coupling between electromagnetic field and intersubband excitations bidimensional electron gas. Our theory, based on electrical dipole gauge, applies generally to an arbitrary quantum heterostructure embedded in multilayer waveguide or microcavity. show that gauge Hamiltonian takes into account Coulomb interactions system, without need adding extra terms Hamilitonian. Furthermore, bright system appear as many-body collective plasmon modes,...
One of the main challenges for future quantum information technologies is miniaturization and integration high performance components in a single chip. In this context, electrically driven sources nonclassical states light have clear advantage over optically ones. Here we demonstrate first semiconductor source photon pairs working at room temperature telecom wavelengths. The device based on type-II intracavity spontaneous parametric down-conversion an AlGaAs laser diode generates 1.57 μm....
A quantum-cascade long-wavelength infrared laser based on superlattice active regions has been demonstrated. In this source, electrons injected by tunneling emit photons corresponding to the energy gap (minigap) between two conduction bands (minibands). distinctive design feature is high oscillator strength of optical transition. Pulsed operation at a wavelength about 8 micrometers with peak powers ranging from approximately 0.80 watt 80 kelvin 0.2 200 demonstrated in 1-nanometer-thick...