All-optical Logic NOR Gate Research Articles

Design and analysis of all-optical logic NOR gate based on linear optics

Design and analysis of all-optical logic NOR gate based on linear optics

Research on output characteristics based on QD-SOA and QD-RSOA cross gain modulation all-optical logic NOR gate

Research on output characteristics based on QD-SOA and QD-RSOA cross gain modulation all-optical logic NOR gate

All-optical logic NOR gate using a single quantum-dot SOA-assisted an optical filter

We thoroughly explore the characteristics of an ultrafast all-optical NOR gate for 160 Gb/s return-to-zero Gaussian data signals using a single quantum-dot semiconductor optical amplifier (QD-SOA) and an optical filter (OF). In this proposed scheme, we employ an optical clock signal as a probe in addition to data signals as pumps between which the Boolean NOR function is executed. By conducting numerical simulations, we investigate and evaluate the effects of various critical factors on the extinction ratio and Q2-factor. This enables us to specify the margins of clock wavelength, peak power of data and clock signals, current density, electron relaxation time from the excited state to the ground state, linewidth enhancement factor, small signal gain of QD-SOA, OF bandwidth and order, the permissible extent of arrival time difference between data signals and clock, and the effect of amplified spontaneous emission. Moreover, we demonstrate that the proposed device can be applied to a multiple-input NOR gate. The results show that the proposed NOR gate can be achieved with both logical correctness and high quality when the specified conditions are satisfied.

Theoretical analysis of soliton NOR gate with semiconductor optical amplifier-assisted Mach–Zehnder interferometer

The performance of soliton all-optical logic NOR gate with semiconductor optical amplifiers (SOAs)-assisted a Mach–Zehnder interferometer is theoretically analyzed and investigated. The dependence of the output quality factor on the soliton characteristics and SOA parameters is studied. The achieved results confirm that the soliton-based all-optical NOR gate is indeed feasible with the proposed scheme at a data rate of 80 Gb/s with logical correctness and acceptable quality.

Simulation of all-optical logic NOR gate based on two-photon absorption with semiconductor optical amplifier-assisted Mach-Zehnder interferometer with the effect of amplified spontaneous emission

The performance of an all-optical NOR gate is numerically simulated and investigated. The NOR Boolean function is realized by using a semiconductor optical amplifier (SOA) incorporated in Mach-Zehnder interferometer (MZI) arms and exploiting the nonlinear effect of two-photon absorption (TPA). If the input pulse intensities is adjusting to be high enough, the TPA-induced phase change can be larger than the regular gain-induced phase change and hence support ultrafast operation in the dual rail switching mode. The numerical study is carried out by taking into account the effect of the amplified spontaneous emission (ASE). The dependence of the output quality factor (Q-factor) on critical data signals and SOAs parameters is examined and assessed. The obtained results confirm that the NOR gate implemented with the proposed scheme is capable of operating at a data rate of 250 Gb/s with logical correctness and high output Q-factor.

NOR gate based on QD-SOA at 250 Gbit/s

The performance of all-optical logic NOR gate based on quantum-dot- semiconductor optical amplifier (QD-SOA) is simulated. By solving the rate equations of QD-SOAs when incorporated in the arms of a Mach–Zehnder interferometer the performance of NOR gate is numerically investigated. The model takes into account the impact of the amplified spontaneous emission, the input pulse energy and the injection current density on the system’s quality factor. Results show that NOR gate using QD-SOA is capable of operating at speeds of 250 Gbit/s with proper quality-factor.

<inline-formula><math altimg="none" display="inline" overflow="scroll"><mrow><mn>40</mn><mspace width="0.3em" /><mi>Gbit</mi><mo>∕</mo><mi mathvariant="normal">s</mi></mrow></math></inline-formula> all-optical logic NOR gate based on a semiconductor optical amplifier and a filter

A novel all-optical logic NOR gate is presented that is composed of a semiconductor optical amplifier (SOA) and an optical bandpass filter. The NOR gate is successfully experimentally demonstrated at 40 Gbit/s. The experiment result shows good extinction ratio of larger than 12.0 dB with clear and open eye. The NOR gate has a simple configuration and allows photonic integration.

High speed logic gate using two-photon absorption in silicon waveguides

The switching speed of conventional silicon-based optical switching devices based on plasma dispersion effect is limited by the lifetime of free carriers which introduce either phase or absorption changes. Here we report an all-optical logic NOR gate which does not rely on free carriers but instead uses two-photon absorption. High speed operation was achieved using pump induced non-degenerate two-photon absorption inside the submicron size silicon wire waveguides. The device required low pulse energy (few pJ) for logic gate operation.

40 Gbit/s all-optical logic NOR gate based on nonlinear polarisation rotation in SOA and blue-shifted sideband filtering

An all-optical logic NOR gate is presented by exploiting nonlinear polarisation rotation in a semiconductor optical amplifier (SOA) and blue-shifted sideband filtering. The NOR gate is experimentally demonstrated and simulated at 40 Gbit/s. Experimental results show high extinction ratio (ER) of about 12.2 dB with very clear and open eye. Simulation shows the scheme can provide excellent performance. The logic gate has a simple configuration and allows photonic integration.

Ultrafast all-optical NOR gate based on semiconductor optical amplifier and fiber delay interferometer

An ultrafast all-optical logic NOR gate based on a semiconductor optical amplifier (SOA) and a fiber delay interferometer (FDI) is presented. For high-speed input return-to-zero (RZ) signal, nonreturn-to-zero (NRZ) switching windows which satisfy Boolean NOR operation can be formed by properly choosing the delay time and the phase shift of FDI. 40Gb/s NOR operation has been demonstrated successfully with low control optical power. The factors that degrade the NOR operation have been discussed.

Tunable all-optical NOR gate at 10 Gb/s based on SOA fiber ring laser

A novel scheme for a tunable all-optical logic NOR gate is presented that is based on a semiconductor fiber ring laser. In this new configuration a semiconductor optical amplifier is employed not only as the operational medium for cross-gain modulation effect to form a logic gate, but also as the active medium for a fiber ring laser that is designed to replace the continuous-wave light required in many other schemes. Alloptical logic NOR operation is successfully demonstrated experimentally by use of 10 Gb/s nonreturn-to-zero (NRZ) signals. An output extinction ratio higher than 10.3 dB can be obtained over the 40 nm tuning range except for a 4 nm gap around the input wavelength.

All-optical logic NOR gate using two-cascaded semiconductor optical amplifiers

The authors present a novel all-optical logic NOR gate using two-cascaded semiconductor optical. amplifiers (SOAs) in a counterpropagating feedback configuration. This configuration accentuates the gain nonlinearity due to the mutual gain modulation of the two SOAs. The all-optical NOR gate feasibility has been demonstrated delivering an extinction ratio higher than 12 dB over a wide range of wavelength.