Abstract: A low threshold distributed feedback (DFB) laser is constructed for improved performance at subzero temperatures. A loss grating is employed to enhance the probability that lasing occurs near the short wavelength side of the stopband and to counteract the effect of negative gain tilt that occurs when DFB lasers are positively detuned. A method of making DFB lasers from wafers with improved yield for low temperature side mode suppression ratio (SMSR) is also disclosed.

Abstract: A transceiver and method of fabrication where the housing comprises a carrier upon which the source and photodetector are mounted and a cover. The housing includes an integral wall extending between the source and photodetector so as to electrically isolate the two devices. The cover may physically contact the wall to provide grounding for the cover.

Abstract: A distributed Bragg reflector laser is fabricated wherein material defects are produced in the laser's tuning waveguide region. The defects may be created by introducing impurities into the region. The defects increase the non-radiative recombination rate of injected carriers, thereby decreasing FM efficiency and improving RF performance. Injected carrier electrons are substantially separated from injected carrier holes to reduce bimolecular and Auger recombination rates, thus improving tuning range.

Abstract: A low threshold distributed feedback (DFB) laser is constructed for improved performance at subzero temperatures. A loss grating is employed to enhance the probability that lasing occurs near the short wavelength side of the stopband and to counteract the effect of negative gain tilt that occurs when DFB lasers are positively detuned. A method of making DFB lasers from wafers with improved yield for low temperature side mode suppression ratio (SMSR) is also disclosed.

Abstract: The invention is a semiconductor laser, laser module, and method of manufacture. The laser includes an active region having a first refractive index, and at least one confinement layer with a second refractive index, which is lower than the first refractive index. An anti-guiding layer having a third refractive index which is lower than the second refractive index is positioned so that the confinement layer is between the active region and the anti-guiding layer. A cladding layer having a fourth refractive index which is greater than the third refractive index is positioned so that the anti-guiding layer is between the cladding layer and the confinement layer.

Abstract: A DBR laser includes at least one active phase shifting section, at least one gain section, and at least one Bragg section. The DBR laser is fine tuned by phase tuning the active phase shifting section of the DBR laser. Phase tuning the active phase shifting section by current injection provides a change in lasing wavelength opposite the change in lasing wavelength in response to tuning the Bragg section by current injection. This opposing change in wavelength reduces, and can eliminate, unwanted wavelength chirp due to crosstalk, thus improving laser performance by reducing the bit error rate (BER). Further, a DBR laser in accordance with the present invention is tunable without temperature tuning, thus providing much shorter transition times between desired wavelengths than possible with temperature tuning. Also, a DBR laser in accordance with the present invention can be operated at one temperature for all channels.

Abstract: A low threshold distributed feedback (DFB) laser is constructed for improved performance at subzero temperatures. A loss grating is employed to enhance the probability that lasing occurs near the short wavelength side of the stopband and to counteract the effect of negative gain tilt that occurs when DFB lasers are positively detuned. A method of making DFB lasers from wafers with improved yield for low temperature side mode suppression ratio (SMSR) is also disclosed.

Abstract: The invention is a semiconductor device, and a method of fabrication, where a waveguide layer in which light is propagated and an integral photodetector are formed in the device. A light absorbing layer of the photodetector includes a portion of the waveguide layer which is modified to absorb a portion of the light while transmitting the remainder of the light. Additional components, such as a laser, optical amplifier and modulator can be included with the photodetector.

Abstract: An optical laser module exhibits stabilized output power over a range of input bias current and temperatures by utilizing an external Bragg grating with an essentially flat response over the grating bandwidth. The flat response is provided by using a combination of separate external gratings, the gratings exhibit different center wavelengths, with a center wavelength separation of 0.5 nm considered to be optimal.