| المستخلص: |
All-optical processing found a novel field of applications in the optical communications networks. It uses photons to achieve digital computations instead of electrical current since it creates heat in computer systems, which is harmful to the hardware. However, light creates unimportant amounts of heat, replaces slow electronic devices and providing high optical transmission rates. The growth of more powerful processing systems becomes possible through quantum dot (QD) nanostructure. Through this work, ladder-plus-Y double quantum dot (DQD) structure was proposed for an all-optical processing. To experience this, density matrix theory is used to write its dynamical equations included wetting layer (WL). The relations for momentum matrix elements are formulated including QD-WL and interdot transitions. A realistic description for both QD and WL wave functions in taking orthogonal zed plane wave in the description of WL performed. A MOAUD software was prepared to solve our problem. The occupation probabilities of this DQD system under the effect of optical pulses where the ground state occupation probabilities of the dots are the highest and the WL was the lowest. The delayed optical pulses reduces the operator probabilities. The pulse width of the applied optical signal is introduced with the density matrix system to study its effect on the output of an all-optical DQD device. Using single qubit, a bad eye-diagram with patterning effect was obtained, then, it is noticed that a developed behavior using DQD structure under the application of three Rabi optical fields at bit rate (10Gbps). A good eye-diagram was obtained under two optical fields, at high bit rate (50Tbps). The possibility of quantum logic gates was predicted by the manipulation of delay time of the applied pulse and through changing the optical fields.
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