NOTE: The THIRD EDITION of this textbook was published on 20 February 2019.

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... Parametric amplification has been studied extensively in the context of nonlinear optics. It has been well established that we can amplify a relatively low power input wave, by using another wave of high intensity, which is called the pump wave, in a nonlinear medium [1][2][3][4]. This theory has been mostly investigated experimentally rather than computationally. ...

... We want to test the accuracy of our computational model by using the experimentally verified theoretical formula in the well-established context of sum frequency generation via nonlinear wave mixing, which is the basis of optical parametric amplification [1,4], in the following example. ...

... The theoretical formula for frequency up-conversion efficiency, which is derived from the solution of nonlinear wave equation that is based on material nonlinearity coefficient, is given as [4]. ℎ . ...

The achievement of wideband high-gain optical parametric amplification has not been shown in micrometer-scale cavities. In this paper we have computationally investigated the optical parametric amplification process in a few micrometer-long dispersive microresonator. By performing a gain medium resonance frequency dependent analysis of optical parametric amplification, we have found that it is possible to achieve a wideband high-gain optical amplification in a dispersive microresonator. In order to account for the effects of dispersion (modeled by the polarization damping coefficient) and the resonance frequency of the gain medium on optical parametric amplification, we have solved the wave equation in parallel with the nonlinear equation of electron cloud motion, using the finite difference time domain method. Then we have determined the resonance frequency values that yield an enhanced or a resonant case of optical parametric amplification, via gain factor optimization. It was observed that if the microresonator is more dispersive (has a lower polarization damping coefficient), then there are more resonance frequencies that yield an optical gain resonance. At these gain resonances, a very wideband, high-gain optical amplification seems possible in the micron scale, which, to our knowledge, has not been previously reported in the context of nonlinear wave mixing theory.

... La propagation de la lumière dans un cristal induit un changement de polarisation − → P qui dépend du champ électrique − → E au travers de la relation tensorielle suivante [82,83] : ...

... Le nioabte de lithium est un matériau diélectrique non magnétique ne possédant ni charges (ρ = 0), ni courant de conduction ( − → j = 0). Dans ce cas là, les équations de Maxwell peuvent s'écrire comme [83,100] : ...

... Les queues évanescentes des modes guidés excitent un mode de propagation du guide adjacent aboutissant ainsi à un échange d'énergie entre les guides, dont la quantité dépend de la longueur d'interaction et de la distance entre les guides [116]. Soient E 1 (z), E 2 (z) les champs électriques se propageant dans deux guides d'ondes distincts : Si l'on suppose les guides sans pertes, l'évolution temporelle des champs sous l'effet d'un couplage évanescent s'écrit comme [83] : ...

  • François Mondain

Les récents progrès de la physique quantique en matière de manipulations d'objets quantiques individuels et/ou collectifs promettent une révolution dans les domaines de la communication, de la métrologie, de l'informatique et de la simulation. Plus spécifiquement, l'avènement des nouvelles technologies quantiques repose sur la génération, la manipulation et le contrôle d'états quantiques tels que l'intrication. Découverte il y a plus de 30 ans, la lumière comprimée s'est imposée comme un outil de choix pour la mise en œuvre des technologies quantiques, mais son utilisation souffre encore aujourd'hui d'un manque crucial de compacité, freinant ainsi la croissance de certaines réalisations en photonique quantique.Pour pallier ce problème, nous avons développé une plateforme photonique compacte de génération et de détection de lumière comprimée aux longueurs d'ondes des télécommunications. Elle repose sur le mariage entre les composants à fibre optique standards à 1550 nm et de l'optique intégrée sur niobate de lithium (LiNbO3), permettant d'obtenir un montage compact, facilement reconfigurable sans qu'aucun alignement ne soit nécessaire (plug-and-play). Grâce à cette approche, nous avons pu mesurer jusqu'à -2 dB de compression pour une puissance de pompe continue de 40 mW, ouvrant ainsi la voie vers la réalisation de systèmes compacts de variables continues en dehors du cadre des laboratoires.Afin de mieux comprendre les limites de notre système expérimental, nous nous sommes également intéressés aux propriétés photoréfractives du niobate de lithium, c'est-à-dire à la variation de son indice optique en fonction de l'intensité lumineuse qui le traverse. En régime de variables continues, là où les puissances optiques peuvent être relativement élevées, ces effets peuvent durablement affecter le fonctionnement des circuits photoniques intégrés sur LiNbO3. Pour cette raison, une étude précise de la photoréfraction a également été accomplie afin d'optimiser la génération et la détection de la lumière comprimée sur puce LiNbO3.

... The scheme is general; the specific numerical plots depicted here use the same parameters as Fig. 2d-i along the z-direction in free space, where A x; y; t; z ð Þis its complex envelope 42 , ω 0 is the carrier angular frequency, and k 0 ¼ ω 0 =c is the carrier wavenumber. The free-space propagation is a spatiotemporally shift-invariant linear map from A x; y; t; 0 ð Þto A x; y; t; d ð Þ 43 : ...

... For concreteness, we set a ¼ 1 μm below. We first consider an incident right-circularly polarized Gaussian wave packet with a center frequency ω c ¼ 0:434 2πc=a, a waist radius W 0 ¼ 5 μm, a temporal width t 0 ¼ 0:8 ps 43 , and a Rayleigh range z R ¼ 0:034 mm. The wave packet is normally incident on the device, and its waist is located at the front surface of the slab. ...

We propose the generation of 3D linear light bullets propagating in free space using a single passive nonlocal optical surface. The nonlocal nanophotonics can generate space–time coupling without any need for bulky pulse-shaping and spatial modulation techniques. Our approach provides simultaneous control of various properties of the light bullets, including the external properties such as the group velocity and the propagation distance, and internal degrees of freedom such as the spin angular momentum and the orbital angular momentum.

... where ω P 2 = (ne 2 )/(m e *ε 0 ) (ref. 39 ). The effective mass m e *, scattering rate Γ and static permittivity ε inf used in the finite-difference time-domain simulation were 0.35 × m e , 1.0 × 10 14 rad s -1 and 3.9, respectively, where e is the charge of the electron, m e is the electron mass and ε 0 is the free-space electric permittivity. ...

... For the 3D range mapping in Fig. 6f, which consists of a model car and a human figure (AA3012, MacPherson's), it was necessary to use an APD array because the reflected beams from different angles were focused through a lens on the detector plane with lateral shifts 39 . We thus used a 16 × 5 APD array (Wooriro, Inc.), which has a sensitivity of 2.5 A W -1 , aperture dimensions of 9.6 × 3.0 mm 2 and pixel dimensions of 600 × 600 μm 2 . ...

  • Junghyun Park
  • Byung Gil Jeong Byung Gil Jeong
  • Sun Il Kim
  • Byoung Lyong Choi

Spatial light modulators are essential optical elements in applications that require the ability to regulate the amplitude, phase and polarization of light, such as digital holography, optical communications and biomedical imaging. With the push towards miniaturization of optical components, static metasurfaces are used as competent alternatives. These evolved to active metasurfaces in which light-wavefront manipulation can be done in a time-dependent fashion. The active metasurfaces reported so far, however, still show incomplete phase modulation (below 360°). Here we present an all-solid-state, electrically tunable and reflective metasurface array that can generate a specific phase or a continuous sweep between 0 and 360° at an estimated rate of 5.4 MHz while independently adjusting the amplitude. The metasurface features 550 individually addressable nanoresonators in a 250 × 250 μm² area with no micromechanical elements or liquid crystals. A key feature of our design is the presence of two independent control parameters (top and bottom gate voltages) in each nanoresonator, which are used to adjust the real and imaginary parts of the reflection coefficient independently. To demonstrate this array's use in light detection and ranging, we performed a three-dimensional depth scan of an emulated street scene that consisted of a model car and a human figure up to a distance of 4.7 m.

... Cuando se presenta el fenómeno de la reflexión total interna en estructuras cilíndricas o rectangulares, estas confinan la luz en su interior y son capaces de transportar la radiación a lo largo de la estructura debido a las múltiples reflexiones en su interior [Saleh, 1991]. El caso más conocido son las fibras ópticas, sin embargo, esto ocurre también en otras estructuras cerradas de diferente geometría, las cuales de manera general son denominadas como sistemas de guías de onda [Snyder, 1983] o guías de luz, cuando la radiación que se propaga en el interior se halla en el rango de la luz visible [Okamoto, 2000]. ...

... En la figura 1, se esquematiza este fenómeno. Para describir completamente la propagación de luz a través de guías de onda, se requiere también conocer dos conceptos más: la apertura numérica (NA) y el ángulo de aceptancia de la guía ( ) [Saleh, 1991]. Estos conceptos proporcionan ~3~ información respecto al ángulo máximo que debe existir entre la luz que se está ingresando en la guía y la normal a la superficie de entrada de la guía, para garantizar que se alcance el ángulo crítico al interior del medio. ...

  • Angel Vergara-Betancourt Angel Vergara-Betancourt
  • Oscar Javier
  • Zapata Nava
  • Castelán Camacho

This paper analyzes the propagation of light in cylindrical structures of polymethylmethacrylate (PMMA). Under different operating scenarios and taking advantage of the property of total internal reflection, the efficiency of light transmission in this type of material is studied. An experimental arrangement consisting of light sources, optical elements, cylindrical acrylic structures and an optical power meter Its uses. For experimental tests, a monochromatic light source and white light were used. The light propagation was performed, modifying conditions such as angle of incidence, lighting distance, structure geometry, thermal conditions, among others and the optical output power was measured. The results allow us to determine the possibility of using these types of structures for the development of interior concentration, conduction and natural lighting systems. The above, as an alternative to the use of optical fibers in natural lighting systems.

... However, the relative distance of the resonances in the forbidden band to the band edges remains almost constant, when the angle of incidence varies from 0 • to 90 • (see Figure 11). By contrast, in a Fabry-Pérot resonator the cavity resonances tend to cross the forbidden band as function of the angle of incidence, while the free spectral range remains constant (Saleh and Teich, 2007). ...

  • Manuel R Gonçalves Manuel R Gonçalves

Thin films of noble metals with thickness smaller than the wavelength of light constitute one of the most investigated structures in plasmonics. The fact that surface plasmon modes can be excited in these films by different ways and the simplicity of fabrication offer ideal conditions for applications in nanophotonics. The generation of optical modes in coupled Fabry-Pérot planar cavities and their migration to hyperbolic metamaterials is investigated. Coupled Fabry-Pérot cavities behave as simple coupled resonators. When the intra-cavity media have different refractive indices in two or more coupled cavities resonance anti-crossings arise. The application of this kind of strong coupling in sensing is foreseen. Beyond the cavity modes excited by propagating waves, also long range plasmonic guided modes can be excited using emitters or evanescent waves. A periodic structure made by multiple plasmonic films and dielectrica supports bulk plasmons, of large propagation constant and increasing field amplitude. The optical response of these structures approaches that of the hyperbolic metamaterial predicted by the effective medium theory. Light can propagate with full transmission in a structure made of a photonic crystal based on quarter wavelength layers and a second photonic crystal with an overlapping forbidden band, but presenting a non-trivial topological phase achieved by band inversion. This is due to excitation of optical Tamm states at the boundary between both crystals. The extension to multiple optical Tamm states using dielectric and plasmonic materials and the symmetries of the edge states is investigated.

  • Peng Wan
  • Mingming Jiang
  • Tong Xu
  • C. X. Kan C. X. Kan

Semiconductor micro/nanostructures with broad bandgap can provide powerful candidates for fabricating ultraviolet photodetectors (PDs) due to their proper bandgap, unique optoelectronic properties, large surface-to-volume ratio and good integration. However, semiconducting micro/nanostructures suffer from low electron conductivity and abundant surface defects, which greatly limits their practical application in developing PDs. In this work, an ultraviolet PD consisting of single Ga-doped ZnO microwire (ZnO:Ga MW) and p-type poly(3,4ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) was designed. When exposed to ultraviolet illumination, the PD exhibits excellent performance (responsivity ∼ 185 mA/W, detectivity ∼ 2.4 ×1011 Jones, and fast response speed of ∼ 212 μs for rise time and ∼ 387 μs for decay time) under self-driven conditions. Compared with that of an undoped ZnO MW-based PD, the responsivity and detectivity of ZnO:Ga MW/PEDOT:PSS PD are significantly enhanced over 400% and 600%, respectively. Due to the incorporation of Ga element, the charge transport properties of a ZnO:Ga MW, specifically for the mobility, are effectively enhanced, which can substantially facilitate the generation, separation, transport and harvest efficiency of photo-generated carriers in the as-fabricated PD. Besides, the Ga-incorporation improves the crystalline quality of MWs and reduces surface state density, further suggesting a high-quality ZnO:Ga MW/PEDOT:PSS heterojunction. This work provides a potential approach for designing high-performance self-powered ultraviolet PDs from the aspect of enhancing carrier transport through fine doping.

In this paper, we investigated two-dimensional (2D) and three-dimensional (3D) finite element method (FEM) simulations to provide ultrasensitive gas sensors based on silicon-on-insulator (SOI) slotted photonic wire structures in the mid-IR spectral region, tuned for the wavelength 3.392 \(\upmu \hbox {m}\). The proposed optical microstructures have the ability to detect methane gas in the environment in addition to sensing the gas flux from the hole/slot regions with a very high sensitivity (\({S} = 2.97\)) through a very high confinement of the electric field in the photonic wire slot region that leads to an increase in the interaction of light with gas. To further boost the sensitivity of the SOI slotted photonic wire structure to the methane gas, we designed an optical microcavity in the photonic crystal (PhC) slotted structure. This microcavity can sense the smallest methane gas level \((0.36062\,\upmu \hbox {m}^{2})\) with high sensitivity (\({S}= 27.45\)), by means of strengthening the high-quality factor cavity mode and reduction of effective modal volumes. In addition, the ultra-wide bandgap (\(1.9\,\upmu \hbox {m}\)) obtained from Bragg mirrors of the simulated microcavity structures can facilitate us to extend the sensing in a wide range of wavelengths.

  • Stephen Rolt Stephen Rolt

The refractive index variation of glasses with wavelength, or dispersion, produces a variation in the refracted angle with wavelength and results in spatial dispersion of the light with respect to wavelength. This chapter considers dispersive prisms. Before examining in detail the behaviour of modern diffractive components, it briefly describes the dispersive properties of a simple prism. The chapter also considers the operation of a prism that is established under the so‐called minimum deviation condition. Diffraction gratings are simple periodic structures that spatially disperse light by diffraction. Ruled gratings are produced by precision single point diamond machining. By contrast, holographic gratings are formed by a photolithographic process. Diffractive optics produce anomalous dispersion. An aspect of the prism refraction process is the beam magnification produced by the prism. The corner cube retro‐reflector finds many applications in industrial and laboratory alignment applications.

  • Stephen Rolt Stephen Rolt

In the treatment of electromagnetic wave propagation it has been maintained that the amplitude of the wave disturbance is a scalar quantity. However, the physical quantities that underlie the amplitude are the electric and magnetic fields. This chapter looks at the underlying structure of optical materials that contribute to refractive properties. In anisotropic materials, such as crystals, not all directions are equivalent, and these internal dipoles are more readily created where the imposed electric field is in certain specific orientations. The effect is that the refractive index of the material varies with the direction of the imposed electricfield, or polarisation. This effect is known as birefringence. The chapter also provides information on polarisation devices such as waveplates and polarising crystals. By analogy with uniaxial materials, a small uniaxial stress condition may be imposed on a glassy material which, in turn, produces a uniaxial strain in the material. This is stress induced birefringence.

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