Investigation into the integration of a resonant tunnelling diode and an optical communications laser: model and experiment

A resonant tunnelling diode has been monolithically integrated with an optical communications laser [the resonant tunnelling diode (RTD-LD)] to form a simple optoelectronic integrated circuit (OEIC) that is a novel bistable device suitable for an optical communications system. The RTD-LD was based on a ridge-waveguide laser structure and was fabricated from an InAlGaAs-InP epi-wafer grown by molecular beam epitaxy; it emitted at around 1500 nm. Voltage controlled optical-electrical switching and bistability were observed during the characterisation of the RTD-LD - useful features for a fibre-optic communications laser. Optical and electrical simulations of the RTD-LD were carried out using the circuit simulation tool PSPICE. In addition, a discrete component version of the RTD-LD was constructed which exhibited optical power oscillations, and along with the results of the simulations, gave insight into the operating principles of the monolithically integrated RTD-LD

Integration of a resonant tunneling diode and an optical communications laser

We report on the first integration of a resonant tunneling diode and an optical communications laser operating at around 1.5 /spl μm. We demonstrate its low-frequency bistable operation and model its electrical characteristics

Quantum cascade lasers with an integrated polarization mode converter

We discuss the design, fabrication and characterization of waveguide polarization mode converters for quantum cascade lasers operating at 4.6 μm. We have fabricated a quantum cascade laser with integrated polarization mode converter that emits light of 69% Transverse Electrical (TE) polarization from one facet and 100% Transverse Magnetic (TM) polarization from the other facet

A liénard oscillator resonant tunnelling diode-laser diode hybrid integrated circuit: model and experiment

We report on a hybrid optoelectronic integrated circuit based on a resonant tunnelling diode driving an optical communications laser diode. This circuit can act as a voltage controlled oscillator with optical and electrical outputs. We show that the oscillator operation can be described by Liénard's equation, a second order nonlinear differential equation, which is a generalization of the Van der Pol equation. This treatment gives considerable insight into the potential of a monolithic version of the circuit for optical communication functions including clock recovery and chaotic source applications

Resonant Tunnelling Optoelectronic Circuits

Nowadays, most communication networks such as local area networks (LANs), metropolitan area networks (MANs), and wide area networks (WANs) have replaced or are about to replace coaxial cable or twisted copper wire with fiber optical cables. Light-wave communication systems comprise a transmitter based on a visible or near-infrared light source, whose carrier is modulated by the information signal to be transmitted, a transmission media such as an optical fiber, eventually utilizing in-line optical amplification, and a receiver based on a photo-detector that recovers the information signal (Liu, 1996)(Einarsson, 1996). The transmitter consists of a driver circuit along a semiconductor laser or a light emitting diode (LED). The receiver is a signal processing circuit coupled to a photo-detector such as a photodiode, an avalanche photodiode (APD), a phototransistor or a high speed photoconductor that processes the photo-detected signal and recovers the primitive information signa

Optoelectronic Oscillators for Communication Systems

International audienceWe introduce and report recent developments on a novel five port optoelectronic voltage controlled oscillator consisting of a resonant tunneling diode (RTD) optical-waveguide integrated with a laser diode. The RTD-based optoelectronic oscillator (OEO) has both optical and electrical input and output ports, with the fifth port allowing voltage control. The RTD-OEO locks to reference radio-frequency (RF) sources by either optical or electrical injection locking techniques allowing remote synchronization, eliminating the need of impedance matching between traditional RF oscillators. RTD-OEO functions include generation, amplification and distribution of RF carriers, clock recovery, carrier recovery, modulation and demodulation and frequency synthesis. Self-injection locking operation modes, where small portions of the output electrical/optical signals are fed back into the electrical/optical input ports, are also proposed. The self-phase locked loop configuration can give rise to low-noise high-stable oscillations, not limited by the RF source performance and with no need of external optoelectronic conversion

A tunable single-mode double-ring quantum-cascade laser

The design, fabrication and characterization of a monolithic double-ring quantum- cascade laser (DRQCL) are described. At a wavelength of 4.6 µm, we demonstrate tunable, single-mode operation of a DRQCL and use it as a source for spectroscopy of CO gas