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A system for continuous variable quantum key distribution via a wavelength router is proposed. The Kerr type of light in the nonlinear microring resonator (NMRR) induces the chaotic behavior. In this proposed system chaotic signals are generated by an optical soliton or Gaussian pulse within a NMRR system. The parameters, such as input power, MRRs radii and coupling coefficients can change and plays important role in determining the results in which the continuous signals are generated spreading over the spectrum. Large bandwidth signals of optical soliton are generated by the input pulse propagating within the MRRs, which is allowed to form the continuous wavelength or frequency with large tunable channel capacity. The continuous variable QKD is formed by using the localized spatial soliton pulses via a quantum router and networks. The selected optical spatial pulse can be used to perform the secure communication network. Here the entangled photon generated by chaotic signals has been analyzed. The continuous entangled photon is generated by using the polarization control unit incorporating into the MRRs, required to provide the continuous variable QKD. Results obtained have shown that the application of such a system for the simultaneous continuous variable quantum cryptography can be used in the mobile telephone hand set and networks. In this study frequency band of 500 MHz and 2.0 GHz and wavelengths of 775 nm, 2,325 nm and 1.55 μm can be obtained for QKD use with input optical soliton and Gaussian beam respectively. [ABSTRACT FROM AUTHOR]

We propose two designed systems consist of series of micro ring resonator (MRR) and an add/drop multiplexer in which the optical dark and bright soliton pulse propagating within the nonlinear waveguides can be amplified which can be used in long communication system. The dark or bright soliton is input into designed systems and travels within the waveguide. A continuous soliton pulse is sliced into smaller pulses by the nonlinear effect which is known as chaos. In this way large bandwidth of optical signals can be obtained. The power amplification occurs when the soliton propagates along the MRRs or add/drop systems. The add/drop multiplexer system can itself be used to amplify the optical soliton when the bright soliton is input at the drop part of the system. In this work we have studied the generation of amplified pulse of optical dark and bright soliton when they propagating inside single systems or when they interact and collide during propagation inside an add/drop device. It means that amplified soliton pulse also can be obtained when two types of soliton i.e., dark and bright soliton collide with each other in a same system. In such a way the amplified dark soliton or bright soliton can be used to perform the long distance link. [ABSTRACT FROM AUTHOR]

In this study, new system of quantum cryptography for network communication is proposed. Optical tweezer in the form of potential well can be generated and propagate via a nonlinear modified add/drop interferometer system incorporated with a beam splitter and a time division multiple access (TDMA) system wherein the transportation of quantum binary codes is performed. To increase the channel capacity and security of the signals, the multiplexer system is proposed. Beam splitters can be used to generate high capacity binary codes within the proposed system. We have proposed the use of ring resonator to form the optical potential wells. The multiplexed potential wells are formed and transmit via an available link, where the logic codes can be sent out with different time, used for high capacity transmission of the secured data. In this work narrow pulses with FHHM of 9.57 nm and 8 nm could be obtained from the drop and through ports of the add/drop interferometer system respectively. The outputs of different center wavelengths are combined and used to generate multiple potential well signals where the multiple signals with FWHM and FSR of 0.8 nm and 5 nm could be obtained respectively. The digital generated codes can be transmitted via communication networks such as time division multiple access (TDMA) system. [ABSTRACT FROM AUTHOR]

A molecular cryptography technique using optical tweezer, is presented. The modified add/drop filter system consisting of one centered ring and one smaller ring on the left side can be used to generate narrow pulse of tweezer. The optical tweezer transports the molecules in the communication network system. Tweezer generated by the dark-Gaussian behavior can be in the form of a potential well. The dark soliton propagates inside nonlinear microring resonator (NMRR) system, where the input Gaussian pulse control the output signal at the drop port of the system. Output optical tweezers can be connected to the quantum signal processing system consisting of a transmitter and a receiver. The transmitter is used to generate the high capacity quantum codes within the series of MRR's and an add/drop filter. The receiver will detect the encoded signals known as quantum bits. The transmitter will generate the entangled photon pair, propagating via an optical communication link. Here, optical tweezer with full width at half maximum (FWHM) of 13.08 and 12.63 nm are obtained at the drop and through ports of the system respectively. These results are in the form of potential well used to be transmitted through quantum signal processor via an optical fink. [ABSTRACT FROM AUTHOR]