In this paper, for the rst time, a high performance hybrid silicon evanescent traveling wave electroabsorption modulator based on asymmetric intra-step-barrier coupled double strained quantum wells active layer is introduced which has double steps at III/V mesa structure. Through this active layer, hybrid silicon evanescent traveling wave electroabsorption modulator will be advantages such as v...

Utilizing the underlying physics of evanescent-wave amplification by a negative-refractive-index slab, it is shown that evanescent waves with specific spatial frequencies can also be amplified without any reflection simply by two dielectric planar waveguides. The simple configuration allows one to take advantage of the high resolution limit of a high-refractive-index material without contact wi...

We demonstrate gas detection based on evanescent-wave photoacoustic (PA) spectroscopy with tapered optical fibers. Evanescent-field instead of open-path absorption is exploited for PA generation, and a quartz tuning fork is used for PA detection. A tapered optical fiber with a diameter down to the wavelength scale demonstrates detection sensitivity similar to an open-path system but with the ad...

Utilizing the underlying physics of evanescent wave amplification by a negative-refractive-index slab, it is shown that evanescent waves with specific spatial frequencies can also be amplified without any reflection simply by two dielectric planar waveguides. The simple configuration allows one to take advantage of the high resolution limit of a high-refractive-index material without contact wi...

Cladded multimode fiber optic tapers are proposed as chemical sensors using evanescent wave absorption. There is no need to strip the cladding; therefore, fabrication is easy and the taper is mechanically stronger than the taper without cladding. The transmission property and evanescent wave absorption are modeled using ray theory and wave theory, respectively. Effects of some parameters on the...

Maximum number of excitation light sources Dependent on the fiber diameter: in general, only one due to the small fiber diameter. Using 5 mm diameter LEDs and a 10 cm long fiber, it is possible to accomodate a total of 20 light sources increasing the amount of signal accordingly. Amount of excitation light available Available from the evanescent wave tail which is a very small portion of the to...

In an interesting paper published in 1949, Schaffner and Toraldo di Francia @1# reported experimental proof of the existence of evanescent ~surface! waves generated by diffraction. Working at the scale of microwaves, they found that the experiment was easier and the results were more accurate, compared to those that had previously been performed in the optical range @2#. Microwaves of about 3 c...

We demonstrate an all-fiber passively Q-switched erbium-doped fiber laser (EDFL) using a gold-nanosphere (GNS) based saturable absorber (SA) with evanescent field interaction. Using the interaction of evanescent field for fabricating SAs, long nonlinear interaction length of evanescent wave and GNSs can be achieved. The GNSs are synthesized from mixing solution of chloroauricacid (HAuCl4) and s...