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A time-division-multiplexing (TDM) system transceiver with 4–channel 10 Gb/s interfaces to achieve 40 Gb/s non-return to zero (NRZ) transmission is presented. The front-end components are implemented in an indium phosphide double hetero-junction bipolar transistor (InP DHBT) technology. They include a 4:1 multiplexer with a voltage controlled oscillator and clock multiplication unit, modulator drivers for electro-absorption and differential lithium-niobate modulators, trans-impedance amplifier, limiting amplifier and 1:4 demultiplexer with clock and data recovery circuit. The transceiver was used to teat optical transmission over a 2.26 km link with a 40 Gb/s, 2³¹-1 pseudo-random bit sequence (PRBS) data. The transmitter achieves better than 12.9 dB extinction ratio, 1 ps added root mean square (RMS) jitter and 4 dBm output power. Without any optical amplification the receiver achieves -9.1 dBm back to back sensitivity at a bit error rate (BER) of 10^-12 and a high dynamic range of 12.5 dBm.

This paper gives a system designer's point of view regarding the emergence of the many new devices that are being considered as possible replacement of the Metal Oxyde Semiconductor Field effect transistor. The first part is a tentative to define criteria for the systemability of nanodevices. The second part is a short overview of the evolution of information processing systems. The third part is a more specific study of the demultiplexing and fault tolerance problems.

In reorientational soft-matter with uniaxial character, such as nematic liquid crystals (NLCs), self-confined beams into spatial optical solitons are graded-index waveguides subject to birefringent walkoff. We investigate a router to be realized in a planar cell with an inhomogeneous distribution of the optic axis. Based on the input beam position, the proposed demultiplexer can direct the soliton and the copolarized guided-wave signal(s) to various output ports, enhancing the transverse separation of the exit channels and therefore minimizing crosstalk. Both the soliton and the signal(s) maintain their phasefronts normal to launch and exit wavevectors, allowing for excellent coupling into output channels/fibers at the device exit.

In this paper, an ultra-compact high capability silicon-based waveguide with a high nonlinear coefficient and engineered dispersion was designed for frequency combs generation and demultiplexing of these combs. In the first part of the structure, a silicon waveguide with two zero-dispersion wavelengths, 1552nm and 2350nm, and a length of 4mm was used to generate optical frequency combs using the four-wave mixing method. Considering the high nonlinear coefficient of $91.695{(\mathrm{\text{Wm}})}^{-1}$ in the waveguide, an input pump power of 500mW was applied to the waveguide at near-zero-dispersion wavelengths of 1552nm. The output comb spectrum of the waveguide was obtained after the length of 4mm with a spectral bandwidth of 400nm and a free spectral range of 5nm. Additionally, by similar pumping at wavelengths of 1553nm and 1555nm to this waveguide, optical frequency combs with a free spectral range of 2nm and a spectral bandwidth of 150nm were obtained. In the second part of the structure, to isolate the optical frequency combs, the given waveguide was expanded to generate an SOI demultiplexer with micro-ring resonator filters, which could separate optical frequency combs with the wavelength of 1555nm, 1557nm, 1559nm, and 1561nm due to the selection of suitable values for the radius of the ring resonators. The mean transmission efficiency, spectral bandwidth, and quality factor were obtained to be 99.51%, 0.275nm, and 5675, respectively. The channel spacing in the proposed demultiplexer was 2nm and the minimum and maximum crosstalk were −36dB and −11.3dB.

A time-division-multiplexing (TDM) system transceiver with 4-channel 10 Gb/s interfaces to achieve 40 Gb/s non-return to zero (NRZ) transmission is presented. The front-end components are implemented in an indium phosphide double hetero-junction bipolar transistor (InP DHBT) technology. They include a 4:1 multiplexer with a voltage controlled oscillator and clock multiplication unit, modulator drivers for electro-absorption and differential lithium-niobate modulators, trans-impedance amplifier, limiting amplifier and 1:4 demultiplexer with clock and data recovery circuit. The transceiver was used to test optical transmission over a 2.26 km link with a 40 Gb/s, 2³¹−1 pseudo-random bit sequence (PRBS) data. The transmitter achieves better than 12.9 dB extinction ratio, 1 ps added root mean square (RMS) jitter and 4 dBm output power. Without any optical amplification the receiver achieves −9.1 dBm back to back sensitivity at a bit error rate (BER) of 10⁻¹² and a high dynamic range of 12.5 dBm.

This paper gives a system designer's point of view regarding the emergence of the many new devices that are being considered as possible replacement of the Metal Oxyde Semiconductor Field effect transistor. The first part is a tentative to define criteria for the systemability of nanodevices. The second part is a short overview of the evolution of information processing systems. The third part is a more specific study of the demultiplexing and fault tolerance problems.