Mrs Somaye Eskandari, Dr Mahmood Hoseini Farzad, Dr Mohammad Mahdi Doroodmand, Mr Mahdi Musavi,
year 20, Issue 0 (1-2014)
Abstract
In this paper we try to use the single and multi-wall carbon nano-tube powders (fabricated in chemistry department of Shiraz University and outdoor sources) in order to fabricate a suitable thin films of them on the glass substraits and after this, their drying process is employed. If this semiconductor carbon nano-tubes are indivsually coated on the glass substrate they have an ability to locked the longtitudenal modes of a pulses NdLYAG laser and generate ultra-short pulses. The experimental results obtain in this paper for the shape of the output pulses in the present of this samples show that the obtaining of these short pulses is mostly possible by this method.
Mohammad Najafi Hajivar, Mahmood Hoseini Farzad,
year 24, Issue 0 (3-2018)
Abstract
In this paper, a new structure is proposed to improve the performance of graphene modulators. The performance of the graphene modulators has generated so far depends on the polarization of incident light, so that these modulators modulate TM polarization better than the TE polarization. Responsible for this performance difference is the anisotropy of graphene, which has caused the performance of the common modulators is strongly dependent on polarization. In this paper by adding a graphene layer to the waveguide side-wall, in addition to graphene existing in the top of waveguide, Performance dependency of the modulator to polarization has greatly disappeared. The simulation results indicate that, in addition to eliminating the sensitivity of the modulator to the polarization of light, the overall performance of the modulator has also been significantly improved.
