We have experimentally detected a Peltier effect produced by the current flow 111 ohmic contacts upon integrated circuits. These contacts are small size heat sources which are very useful for investigating integrated circuits. We have characterised their thermal properties with a high resolution interferometric laser probe by measuring absolute thermal expansions. Subpicometric resolution has a...

In this paper, we investigate performance improvements in 10 Gbit/s dispersion supported transmission (DST) systems by partial chirp compensation due to self phase modulation in a travelling wave semiconductor optical amplifier (TWA) used as a booster amplifier. For an unsaturated gain of 20 dB, the system performance is improved by 1.14 dB at 204 km, and by 4.13 dB at 253 km SMF. The improveme...

An all solid-state approach to the precise frequency synthesis and control of widely tunable terahertz radiation by differencing continuous-wave diode lasers at 850 nm is reported in this paper. The difference frequency is synthesized by three fiber-coupled external-cavity laser diodes. Two of the lasers are Pound–Drever–Hall locked to different orders of a Fabry–Perot (FP) cavity, and the thir...

In new optical pulse generator using delayedinterference-signal-wavelength-converter (DISC)-type all-optical gate, we injected sinusoidally modulated light to ring cavity. With this way, externally modulated laser oscillation and mode-locked pulse laser oscillation occurred. These generated pulse’s widths and repetition frequencies are 27 ps, 10.5 GHz and 2.1 ps, 10.5 GHz, respectively. Keyword...

We describe a 5.5W 589 nm source based on a passively mode-locked Nd:YVO4 laser and a multi-stage Lithium Triborate optical parametric amplifier seeded by a tuneable semiconductor laser. We show this system can produce rapidly tuneable, transform-limited pulses in near diffraction-limited beams at 589 nm, useful for Na guide star applications. The attraction of this scheme is that it can be ass...

A new type of optical switching device is developed. For a semiconductor laser amplifier with a shallow-etched bending ridge waveguide, the laser beam could propagate along the bending direction or the straight direction. Switching between the two directions is characterized. With the device fabricated on the substrate with two quantum wells of different widths, switching characteristics are fo...

in this paper, the effects of reflected waves of the facets on the internal optical intensity of semiconductor dfb lasers are investigated. the uniformity of optical intensity along the cavity length is evaluated with flatness parameter. the dependence of this parameter on coupling coefficient, reflectivity and grating phase at the facets is also studied. this investigation shows that in some s...

In this paper we present recent results obtained in the area of monolithically integrated modelocked semiconductor laser systems using generic InP based integration platform technology operating around 1550nm. Standardized components defined in this technology platform can be used to design and realize short pulse lasers and optical pulse shapers. This makes that these devices can be realized o...

Passive electrical circuits whose voltage and current equations are exactly equivalent to the small-signal rate equations of a semiconductor laser are derived to model an electrically modulated laser (verified to be the same as that given in the literature), an optically modulated laser (i.e., a laser used as an optical amplifier), and a multimode laser. These circuits offer a fast and efficien...