A5103494965- Photonic and Optical Devices
- Photonic Crystals and Applications
- Plasmonic and Surface Plasmon Research
- Quantum Information and Cryptography
- Atomic and Subatomic Physics Research
- Spectroscopy and Laser Applications
- Semiconductor Quantum Structures and Devices
- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- GaN-based semiconductor devices and materials
- Advanced Frequency and Time Standards
- Quantum optics and atomic interactions
- Random lasers and scattering media
- Advanced Chemical Sensor Technologies
- Advanced Fiber Laser Technologies
- Optical Coatings and Gratings
- Nanocluster Synthesis and Applications
- Near-Field Optical Microscopy
- Mechanical and Optical Resonators
- Advanced Optical Sensing Technologies
- Laser-Matter Interactions and Applications
- Semiconductor Lasers and Optical Devices
- Photocathodes and Microchannel Plates
- Nonlinear Optical Materials Studies
- Radiation Detection and Scintillator Technologies
Swiss Center for Electronics and Microtechnology (Switzerland)
2012-2024
Observatoire Cantonal de Neuchâtel
2017-2020
École Polytechnique Fédérale de Lausanne
2003-2015
Eindhoven University of Technology
2008-2012
Los Alamos National Laboratory
2004-2011
Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine
2009-2011
Nanocomposite materials provide the possibility for multifunctional properties in contrast with their more-limited single-component counterparts. Here, we report synthesis and characterization of first all-inorganic core/shell hybrid magnetic-optical nanoparticle, cobalt/cadmium selenide. The nanocrystals are prepared a facile one-pot reaction, microstructure is analyzed using low- high-resolution transmission electron microscopy. Using magnetic optical characterization, demonstrate...
We study inverted core/shell nanocrystals (NCs) in which a core of wide gap semiconductor (ZnSe) is overcoated with shell narrower (CdSe). By monitoring radiative recombination lifetimes for series these NCs fixed radius and progressively increasing thickness, we observe continuous transition from Type-I (both electron hole wave functions are distributed over the entire NC) to Type-II (electron spatially separated between core) back primarily reside shell) localization regimes. These...
Size-controlled spectral tunability and chemical flexibility make semiconductor nanocrystals (NCs) attractive as nanoscale building blocks for color-selectable optical-gain media. The technological potential of NCs lasing materials is, however, significantly diminished by highly efficient nonradiative Auger recombination multiexcitons leading to ultrafast decay optical gain. Here we explore a novel approach achieve NC in the Auger-recombination-free regime using type II heterostructures that...
We experimentally observe a sizable and reversible spectral tuning of the resonances two-dimensional photonic crystal microcavity induced by introduction subwavelength size glass tip. The comparison between experimental near-field data, collected with $\ensuremath{\lambda}∕6$ spatial resolution, results numerical calculations shows that shift tip is proportional to local electric field intensity cavity mode. This observation proves electromagnetic density states in can be directly measured...
We demonstrate the nonresonant magnetic interaction at optical frequencies between a photonic crystal microcavity and metallized near-field microscopy probe. This can be used to map control component of modes. The metal coated tip acts as microscopic conductive ring, which induces response opposite inducing field. resulting shift in resonance frequency measure distribution field intensity structure fine-tune its via components.
We report a study of the quantum dot (QD) emission in short photonic crystal waveguides. observe that photoluminescence intensity and decay rate are strongly enhanced when energy is resonance with Fabry-Perot (FP) cavity modes slow-light regime dispersion curve. The experimental results agreement previous theoretical predictions further supported by three-dimensional finite element simulations. Our show combination slow group velocity provide an avenue to efficiently channel photons from...
We describe the design and characterization of a fiber-coupled double-channel single-photon detection system based on superconducting detectors (SSPD), its application for quantum optics experiments semiconductor nanostructures. When operated at 2-K temperature, shows 10% efficiency 1.3-¿m wavelength with dark count rate below 10 counts per second timing resolution <100 ps. The short recovery time absence afterpulsing leads to counting frequencies as high 40 MHz. Moreover, low allows...
We report by means of near-field microscopy on the coupling between two adjacent photonic crystal microcavities. Clear-cut experimental evidence spatial delocalization coupled-cavity optical modes is obtained imaging electromagnetic local density states. also demonstrate that it possible to design structures with selective different having orthogonal extensions
CdSe semiconductor nanocrystal quantum dots are assembled into nanowire-like arrays employing microtubule fibers as nanoscale molecular "scaffolds." Spectrally and time-resolved energy-transfer analysis is used to assess the assembly of nanoparticles hybrid inorganic biomolecular structure. Specifically, we demonstrate that a comprehensive study energy transfer between dot pairs on biotemplate and, alternatively, dyes embedded in scaffold comprises powerful spectroscopic tool for evaluating...
We present a spectral tuning mechanism of photonic crystal microcavities based on microfluidics. The microinfiltration with water one or few cavity holes and its subsequent controlled evaporation allow us to tune the resonances in range larger than 20 nm, subnanometer accuracy, we also observe that addition microcavity region improves quality factor Q.
We report on polarization sensitive imaging of two-dimensional photonic crystal microcavity modes. By using a near-field scanning optical microscope with setup, it is possible to selectively map, resolution beyond the diffraction limit, each electric field component in plane sample. In addition, simultaneous analysis photoluminescence maps different channels allowed us obtain important insight microscopy detection mechanism. Finite difference time domain simulations confirm experimental results.
A method to achieve photoinduced tuning of PhC nanocavity modes is discussed and implemented. It based on light induced oxidation in air atmosphere with very low thermal budget which produces a local reduction the GaAs membrane effective thickness large blueshift modes. also shown that green much more efficient inducing micro-oxidation respect near infrared light. The observed behaviour attributed oxide growth promoted by photoenhanced reactivity.
We report ultra-low phase-noise microwave generation at a 9.6 GHz carrier frequency from optical combs based on diode-pumped solid-state lasers emitting telecom wavelength and referenced to common cavity-stabilized continuous-wave laser. Using novel fibered polarization-maintaining pulse interleaver, single-oscillator floor of -171 dBc/Hz 10 MHz offset has been measured with commercial PIN InGaAs photodiodes, constituting record for this type detector. Also, direct measurement the stabilized...
We present the local polymer infiltration of planar photonic crystal cavities via a maskless laser-writing technique. After air holes with UV-curable monomer focused laser is used to locally polymerize in selected at cavity boundaries. show that modes different symmetries can be differently tuned depending on size and position infiltrated region around cavity.
A complete control of the coupling between modes two photonic crystal microcavities is obtained by using a combination several local tuning techniques. By and controlled modification one cavity we are able to bring into resonance with different polarization spatial distribution, producing heteroatomic molecules. Clear anticrossing observed, denoting mode hybridization which in very good agreement finite difference time domain calculations.
A fine control of a photonic molecule is obtained by nanofluidic techniques. The coupling condition between the modes two crystal nanocavities modified spectrally tuning each single resonator. Clear mode anticrossing and transition from localized to delocalized states are observed. detuning induced disorder, always present in real device, experimentally compensated locally modifying environment cavity.
Abstract Air pollution is one of the largest risk factors for disease or premature death globally, yet current portable monitoring technology cannot provide adequate protection at a local community level. Within TRIAGE project, smart, compact and cost-effective air quality sensor network will be developed hyperspectral detection gases which are relevant atmospheric dangerous human health. The based on mid-infrared supercontinuum source, providing ultra-bright emission across 2–10 µ m...
We report on a nonlinear way to control and tune the dielectric environment of photonic crystal microcavities exploiting local heating induced by near-field laser excitation at different powers. The temperature gradient due optical absorption results in an index refraction which modifies surroundings cavity shifts modes. Reversible tuning can be obtained either changing power density or exciting points microcavity.
The detailed design of the Swiss Miniature Atomic Clock (Swiss-MAC) was presented by CSEM in 2012. This paper describes progress made meantime towards realization integrated Swiss-MAC, presenting a first prototype showing preliminary but very promising performances.
Abstract Quantum optics largely relies on the fundamental concept that diffraction and interference patterns of a multi-partite state are determined by its de Broglie wavelength. In this paper we show is still true for mixed with one sub-system being in classical coherent entangled state. We demonstrate quantum-classical light discrimination using wavelength states all parameters same.
This paper presents the results of ESA funded C-MAC activity, started mid-2015 and currently in assembly testing phase. The objective activity is to develop an innovative low-cost ceramic-based physics package (PP) for ultra-low power miniature atomic clocks (MACs) with flat form factor future portable devices (GNSS receiver, smartphone, tablet, laptop, etc.) high-end demanding applications like onboard satellites.