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Real time measurements of fluctuations during nonlinear pulse propagation in optical fibers present significant challenges, yet there is clearly much insight to be obtained in explicitly measuring shot-to-shot variation in pulse characteristics. This is especially the case in optical supercontinuum (SC) generation, where many different processes contribute to the spectral broadening, and isolating...
Solitons are ubiquitous in nonlinear optics and are well known to radiate away energy when perturbed. This radiation is commonly called a dispersive wave (DW) because it spreads temporally due to chromatic dispersion [1]. It can also be interpreted as Čerenkov radiation. A classic example is DW emission by Kerr optical fiber solitons in presence of high-order dispersion. This case has important applications...
A laser frequency comb allows the conversion of the very rapid oscillations of visible light of some 100s of THz down to frequencies that can be handled with conventional electronics. This capability has enabled the most precise laser spectroscopy experiments yet, that allowed testing quantum electrodynamics, to determine fundamental constants and to search for possible slow changes of these constants...
Nonlinear hybrid silicon-plasmonic (HSP) waveguides are comprised of a low-index dielectric with a high nonlinear-index (n2) occupying the area between a metal and a high-index dielectric, i.e. silicon. Fusing plasmonic and index-contrast guiding mechanisms [1], HSP waveguides can increase the lateral confinement thus boosting the nonlinear parameter (γ); this effect is maximized as the gap between...
3D metallic nanostructures offer unique light-manipulation functionalities for nanophotonics, including isotropic magnetic optical response, dispersion manipulation, and engineering of the complex polarization state of light. Particularly, chiral metamaterials offer remarkable opportunities to manipulate the polarization properties of circularly polarized light, leading to pronounced optical activity...
Science Magazine listed transformation optics among the top 10 science insights of the decade 2000–2010. The tutorial gives an introduction into this subject that may, literally, transform optics.
Several security related applications are based on laser sources emitting in the short wavelength infrared (SWIR, 1.4–3 μm) or the mid wavelength infrared (MWIR, 3–5 μm) regime. Depending on the requirement of the specific application, the simultaneous use of multiple spectral lines at different wavelengths is often required. The simplest way to achieve multi wavelength emission is the combination...
This work deals with high energy eye-safe lasers for long-distance active imagery purpose. Direct resonant pumping of erbium appears as a very promising technique, either at 1530nm with fibre lasers or at 1470nm with laser-diodes [1-3]. Indeed, the long lifetime (5–10ms) of the upper laser level ensure a favourable energy storage capability and the resonant scheme leads to a reduced thermal loading...
Among gold nanoparticles, gold nanorods (AuNRs) display two surface plasmon resonances (SPR) corresponding to the oscillation of the quasi-free electrons in directions parallel (longitudinal SPR) and perpendicular (transverse SPR) to the rod longer axis. The longitudinal resonance can be tuned from green to near infrared by modifying the nanorod aspect ratio (AR): the higher AR, the smaller the LSPR...
Control over spontaneous emission has many applications ranging from solar energy harvesting and lasing, to single-photon sources for quantum information and telecommunication. As described by Fermi's “golden rule”, the radiative decay rate of the emitters is proportional to the local density of optical states (LDOS) [1,2]. The LDOS counts all available optical modes and is interpreted as the strength...
Recent studies have demonstrated that it is possible to modify the properties of metamaterials by electromagnetic waves via inducing mechanical deformations of samples and therefore changing material properties. As an example, optical rotation of chiral particles was demonstrated [1], and a rich variety of nonlinear behaviour was achieved with magneto-elastic metamaterials [2]. The range of possible...
Light incident on a scattering medium is redistributed over transport channels that either transmit through or reflect from the medium. We perform experiments aiming at finding individual transport channels of extremely strongly scattering materials. A small number of transport channels in a scattering sample are open with transmission coefficient close to 1; field transmission mainly takes place...
Semiconductor quantum dots (QDs) have very recently become candidate building blocks of a quantum information technology, after the experimental proof of full single-qubit control. An essential requirement of the quantum information paradigm is the possibility for two qubits to interact coherently in a controlled fashion. Given the recent success in embedding QDs in Photonic Crystal (PHC) devices,...
A single two-level system constitutes an extremely non-linear optical medium, where the interaction with a first single photon modifies the transmission probability for a second photon. The main difficulty to implement a single photon switch using this property is to ensure that a gate single photon will interact with the quantum emitter with a near-unity probability. In the solid state, all-optical...
It was recently demonstrated that various novel, ultrafast strong-field processes can take place in the field of few-cycle propagating surface plasmon wavepackets such as tunnelling (strong-field) photoemission even at low laser intensities or keV electron acceleration [1,2]. The (moderate, less than xlO) field enhancement at nano-sized, typically non-plasmonic metallic tips also resulted in a set...
In plasmonic metamaterials, light is usually coupled to surface plasmon-like modes that allow modification of both linear optical properties and enhance the metamaterial's effective nonlinearities [1-3]. Recently plasmonic metamaterials based on nanorod arrays and split-ring resonators have indeed shown a strong and fast nonlinear behaviour [2,3]. These fast nonlinearities have been attributed to...
The observation of coherent light-matter interaction in an ensemble of oscillators requires that a macroscopic number of individual oscillators retain a fixed phase relationship for a significant amount of time. In the condensed phase, given the high density and consequently a very fast dephasing time T2, observable effects are usually limited to low temperatures. We study experimentally and numerically...
Sharp nanometer-sized metallic tips recently emerged as a test bed for exploring strong-field phenomena such as high-harmonic generation and photoemission [1-4]. When being illuminated with few-cycle laser pulses of sufficient field strength, optical field enhancement at the tip apex results in tunnelling of electrons out of the tip. The acceleration of these electrons within the local near-field...
In the interaction between light and matter, linear momentum can be transferred from electromagnetic waves to particles to generate so-called optical forces. Recently, it has been suggested that optical gradient forces can be used to actuate nanophotonic devices since measurable displacements can be achieved [1]. The typical setup consists of two waveguides positioned in each other's vicinity such...
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