in this study, the nonlinear optical properties and optical limiting performance of the silver nanoparticles (agnps) in distilled water are investigated. the nonlinear absorption coefficient of the colloid is measured by the z-scan technique. the optical limiting behavior of the agnp suspension is investigated under exposure to nanosecond laser pulses at 532 nm. the results show that nonlinear ...

Abstract We present the use of a power limiting apparatus to evaluate ultrafast optical nonlinearities transparent liquids (water and ethanol) in femtosecond filamentation regime. The setup has been previously employed for same purpose, however, longer pulsewidth (> 20 ps) regime, which leads an ambiguous evaluation critical self-focusing. uncertainty originates from existence threshold brea...

In this paper, a new spreading technique for intensity modulation direct detection fiber-optic code-division multiple-access (FO-CDMA) communication systems is proposed. This new spreading technique is based on generalized optical orthogonal codes (OOC) with large cardinality and minimal degradation in performance when compared with a more optimum system, namely, an optical CDMA system using OO...

Time-domain numerical analysis of nonlinear propagation in Slow-Wave-Structures, focused on the interplay of enhanced third-order nonlinearity with chromatic dispersion has been carried on. In dependence on the operating conditions, a tunable optical oscillator/pulse train generator and an optical limiter have been designed. Morphological inspection and functional characterization at λ=1.5 μm o...

AbsfractThis paper computes the probabilities of detection and false alarm for a pseudonoise (PN) sequence code lock detector when a strong radio frequency interference (RFI) hits the communications link. A soft-limiter, a hard-limiter, and no limiter at the front-end of the receiver are considered. Both continuous wave (CW) type RFI and pulse type RFI are analyzed. It is shown that a soft-limi...

We propose a scheme for an optical limiter and switch of the transmitted light intensity in an array of subwavelength metallic slits placed on a nonlinear Kerr-type dielectric substrate of finite thickness, where the geometrical parameters are designed for operation at telecom wavelengths. Our approach is based on the abrupt changes of the output light intensity observed in these systems near t...

We investigate the nonlinear power transfer characteristics of a silicon photonic microring resonator. We show that the microring device behaves as a power limiter if the roll-off tail of its resonance is steeper than a simple Lorentzian lineshape. OCIS codes: (230.4110) Modulators; (230.4555) Coupled Resonators; (200.4650) Optical Interconnects.

We present a pump-and-signal-resonant optical parametric oscillator that provides 25 dB of amplitude noise suppression of the transmitted pump beam from dc to 20 kHz. The upper frequency range of the optical limiter increases as the pump power is increased, up to 1 MHz with 580 mW of input power. The amount of noise suppression is limited by pump-depletion effects. The upper frequency range is ...

Focusing and defocusing of laser light has been observed for many years. Optical Kerr type materials exhibit this effect only for high intensities. We show experimental evidence that photorefractive materials can also produce dramatic focusing and defocusing. Whereas Kerr materials produce this effect for high intensities, photorefractive materials produce these effects independent of intensity...