Techniques to produce 100 percent male tilapia

A discussion is presented on endocrine sex reversal and chromosome manipulation techniques for producing 1005 male tilapia. Details are given of methods for the administration of steroids and the induction of ploidy.

Measurement of polarisation dependent all-optical nonlinearity in GaAs/AlGaAs quantum well waveguides far from the bandedge

The all-optical nonlinearity of a quantum well waveguide is studied by measuring the intensity dependent transmission through a Fabry-Perot cavity formed around the guide. Values for the nonlinear refractive index coefficient, η 2, at a wavelength of 1.06μm are obtained for light whose polarisation is either parallel or perpendicular to the quantum well layers. A simple measurement to estimate the two photon absorption coefficient, B2, using relatively low optical power levels is also described.

Polarisation dependent all-optical nonlinearity far from the bandedge in active GaAs/AlGaAs quantum well waveguides

This paper describes a measurement on a GaAs quantum well waveguide with a high built in field across the quantum wells at a wavelength far from the bandedge. The device structure used for the measurement has been fabricated at STC Technology Ltd and is that of a standard laser ridge structure. In fabrication double heterostructure layers are grown on a [001] n + GaAs substrate, with the active region containing two intrinsic GaAs quantum wells of 10nm thickness separated by 10nm. A 4μm wide ridge is etched to provide transverse optical guiding. The experimental work has involved the use of 1.06μm wavelength light from a Q-switched Nd:YAG laser. Any induced change in refractive index is determined by measuring the change in transmission of the quantum well waveguide Fabry-Perot cavity. The waveguide is placed on a Peltier temperature controller to allow thermal tuning.

35 GHz passive mode-locking of InGaAs/GaAs quantum dot lasers at 1.3 μm with Fourier-limited pulses

We report 35 GHz passive mode-locking and 20 GHz hybrid mode-locking of quantum dot (QD) lasers at 1.3 μm. Our investigations show ultrafast absorber recovery times and for the first time transform-limited mode-locked pulses. © 2003 Optical Society of America.