Raja Abdullah Raja Ahmad

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We present polymer (PMMA) cladded chalcogenide (As(2)Se(3)) hybrid microwires that realize optical parametric four-wave mixing (FWM) with wavelength conversion bandwidth as broad as 190 nm and efficiency as high as 21 dB at peak input power levels as low as 70 mW. This represents 3-30 × increase in bandwidth and 30-50 dB improvement in conversion efficiency(More)
The inscription of Bragg gratings in chalcogenide (As(2)Se(3)) wires with subwavelength diameter is proposed and demonstrated. A modified transverse holographic method employing He-Ne laser light at a wavelength of λ(w)=633 nm allows the writing of Bragg grating reflectors in the 1550 nm band. The gratings reach an extinction ratio of 40 dB in transmission(More)
INTRODUCTION Ranula is a mucous extravasation cyst which occurs as a result of trauma or obstruction of the sublingual or minor salivary gland or the duct itself. PATIENTS AND RESULTS 14 patients were seen at Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur and Hospital Tunku Ampuan Afzan, Kuantan, Malaysia between 2000 to 2006. There were six(More)
We demonstrate the first optical parametric oscillator (OPO) based on chalcogenide glass. The parametric gain medium is an As(2)Se(3) chalcogenide microwire coated with a layer of polymer. The doubly-resonant OPO oscillates simultaneously at a Stokes and an anti Stokes wavelength shift of >50 nm from the pump wavelength that lies at λ(P) = 1,552 nm. The(More)
We report the observation of modulation instability (MI) in the mid-infrared (mid-IR) spectral region by pumping a hybrid polymer-chalcogenide optical microwire with a femtosecond optical parametric oscillator operating at 2.6 μm. It is further shown that this MI occurs in the normal dispersion regime through negative fourth-order dispersion and leads to(More)
We investigate the onset of nonlinear effects in hybrid polymer-chalcogenide optical microwires and show that they provide an enhanced Kerr nonlinearity while simultaneously mitigating stimulated Brillouin scattering as compared to both chalcogenide and silica optical fibers. It is shown in particular that the polymer cladding surrounding the microwire(More)
The operation of a polarization-mode dispersion monitor insensitive to chromatic dispersion is demonstrated at 40 Gbits/s. The high-speed processing device is based on the Kerr effect and provides an optical power output as a reading of differential group delay. The monitor is compatible with return-to-zero modulation formats at data rates in excess of 40(More)