Related papers: Two-photon absorption in silicon using real densit…
A combined approach of first-principles density-functional calculations and the systematic cluster-expansion scheme is presented. The dipole, quadrupole, and Coulomb matrix elements obtained from ab initio calculations are used as an input…
We report on simulation results that shows optimum photon absorption by superconducting nanowires can happen at a fill-factor that is much less than 100%. We also present experimental results on high performance of our superconducting…
We report on simulations and measurements of the optical absorption of silicon nanowires (NWs) versus their diameter. We first address the simulation of the optical absorption based on two different theoretical methods : the first one,…
UV ice photodesorption is an important non-thermal desorption pathway in many interstellar environments that has been invoked to explain observations of cold molecules in disks, clouds and cloud cores. Systematic laboratory studies of the…
Absorption imaging is a commonly adopted method to acquire, with high temporal resolution, spatial information on a partially transparent object. It relies on the interference between a probe beam and the coherent response of the object. In…
The electronic properties of ultrathin crystals of molybdenum disulfide consisting of N = 1, 2, ... 6 S-Mo-S monolayers have been investigated by optical spectroscopy. Through characterization by absorption, photoluminescence, and…
We show that it is not possible to discriminate two close transparencies without a certain number of photons being absorbed. We extend this to the discrimination of patterns of transparency (images).
We demonstrated the observation of Rb two-photon absorption directly excided by an optical frequency comb at fiber communication bands. A chain of comb spectral control is elaborately implemented to increase the power of the second harmonic…
We demonstrate a silicon photonic dual-polarization phase retrieval receiver. The receiver recovers phase from intensity-only measurements without a local oscillator or transmitted carrier. We design silicon waveguides providing long delays…
Optical absorption plays a central role in optoelectronic and photonic technologies. Strongly absorbing materials are thus needed for efficient and miniaturized devices. There exists, however, a fundamental limit of 50% absorptance for any…
The basic theoretical foundation for the modelling of phonon assisted absorption spectra in direct bandgap semiconductors, introduced by Elliott 60 years ago using second order perturbation theory, results in a square root shaped dependency…
Raman spectra obtained by the inelastic scattering of light by crystalline solids contain contributions from first-order vibrational processes (e.g. the emission or absorption of one phonon, a quantum of vibration) as well as higher-order…
We numerically analyze the use of intense entangled twin beams for ultra-sensitive spectroscopic measurements in chemical and biological systems. The examined scheme makes use of intense frequency-modulated (chirped) entangled beams to…
Multi-photon interference in large multi-port interferometers is key to linear optical quantum computing and in particular to boson sampling. Silicon photonics enables complex interferometric circuits with many components in a small…
The cross section of light absorption by semiconductor quantum dots in the case of the resonance with excitons $\Gamma_6 \times \Gamma_7$ in cubical crystals $T_d$ is calculated. It is shown that an interference of stimulating and induced…
The cyclotron resonance absorption of two-dimensional electrons in semiconductor heterostructures in high magnetic fields is investigated. It is assumed that the ionized impurity potential is a dominant scattering mechanism, and the theory…
We show that a weakly absorbing, strongly scattering (white) medium can be made very strongly absorbing at any frequency within its strong-scattering bandwidth by optimizing the input electromagnetic field. For uniform absorption, results…
Nonlinear optical effects can be enhanced in tapered optical fibers with diameters less than the wavelength of the propagating light. Here we report on the observation of two-photon absorption using tapered fibers in rubidium vapor at power…
Enabling perfect light absorption in ultrathin materials promises the development of exotic photonic devices. Here we demonstrate new strategies that can provide capabilities to rationally design ultrathin (thickness <…
We investigate the nonlinear optical response of a commercial extended-wavelength In$_{0.81}$Ga$_{0.19}$As photodetector. Degenerate two-photon absorption in the mid-infrared range is observed at room temperature using a quantum cascade…