Hybrid buffer and AWG based add-drop optical packet switch

Optical packet switching (OPS) exhibits the ability to be utilized as a data transmission technique for next-generation. The core router/switch plays a significant role in packet routing and buffering in OPS. Arrayed waveguide grating (AWG) is realized as a promising core element for fast optical switching, with its intrinsic capacity to achieve wavelength routing of different wavelengths in parallel. This paper proposes an AWG-based add-drop optical packet switch, including a hybrid buffer, to resolve contention among packets. In a hybrid buffer, both optical and electronic buffers are used for the buffering of contending packets. AWGs are affected by crosstalk that can significantly impair system operation. The physical layer analysis is discussed in the presence of crosstalk, and the performance of the switch is evaluated in terms of bit error rate. The desired minimum input power is calculated for the switch’s correct operation for both optical buffer and electronic buffer. Finally, the packet loss probability (PLP) of the hybrid buffer is examined under various buffering conditions. Results reveal that with the increase in the optical power of the input signal, crosstalk power increases linearly for optical and electronic buffers. The increased crosstalk power is higher for electronic buffers than the optical buffer. The use of electronic memory in the hybrid buffer allows the hybrid buffer to increase its buffer size thus, reducing the PLP.

Optomechanically induced transparency and possible application in a quadratic-coupling optomechanical system with an induced electric field

Tunable optomechanically induced transparency (OMIT) with an induced electric field (IEF) in a quadratic-coupling optomechanical system is theoretically investigated. The system transmission rate under different controlling parameters has been discussed. It is revealed that both phase and group delay of the probe field can be adjusted by the IEF and pump field. Such a system may be used in tunable optical buffer, IEF detector, modulator or other optical devices.

Variable Optical Buffer Using EIT in Three Level System Based on Semiconductor Conical Quantum Dots

A variable semiconductor optical buffer based on the electromagnetically induced transparency (EIT) in a three level conical quantum dot system (CQD) is theoretically investigated. The system is interacting with two (control and signal) laser beams. Signal light with subluminal velocity is possible in such system through the quantum interference effect induced by the control pump field. We investigate the refractive index and absorption spectra of the QD waveguide at different pump levels, which exhibit an optimal pump power for maximum slow-down factor (SDF). The group velocity SDF is theoretically analyzed as a function of the pump intensity at different broadened linewidths. The present study is based on the assumption that the medium is homogeneous. In this paper, a SDF as a function of CQD radius was studied. The simulation results indicate that the SDF increases with decreasing CQD radius.

Optical Buffer Design based on SOA and DCFBG

Presently, research activities are geared towards optical switching technologies that involve all-optical switching, without transformation from optical domain to electronic domain. However, blocking in these systems is a huge problem due to the absence of appropriate optical buffers. In this paper, we propose an optical buffer design based on SOA and DCFBG (dispersion compensation fiber Bragg grating) for contention resolution in all-optically switched networks, and hence improved the power performance of the existing design.