Two-section singlemode lasers based on slots suitable for photonic integration

Abstract

Abstract:Internal conical diffraction by biaxial crystals with aligned optic axes, known as cascade conical diffraction is investigated. Formulae giving the intensity distributions for a cascade conically diffracted Gaussian beam are shown to compare well with experiment for the cases of two biaxial crystals with the same and different lengths and with the second crystal rotated with respect to the first. The effects of placing half wave-plates between crystals are also investigated.

Linewidth Characterization of Integrable Slotted Single-Mode Lasers

“…The Lorentzian linewidth is 840 kHz at an injection current of 130 mA which is realized by using an ultra low noise current source. The linewidth measurements were measured using this low noise current source in the free-space setup in comparison with standard current sources which we used in our previous results [14].…”

“…We have already demonstrated the performance of this laser with high SMSR of more than 50 dB [13]. The linewidth of such lasers was first measured in [14] using a lensed fiber coupling system. However, the back reflection from the lensed fiber coupled into the laser cavity influenced the measurement accuracy.…”

Ten-Channel Wavelength Tunable Single-Mode Laser Array Based on Slots

“…However, fabricating these DFB laser arrays requires both high resolution processing and complex re-growth steps. Recently, by introducing a group of slots into the surface of the ridge on one side of the laser cavity, we have successfully demonstrated single mode lasers can be made completely dependent on a group of slots 3,4 . Such a laser platform is of a single growth, can be fabricated by standard photolithography and is suitable for photonic integration.…”

“…Each laser within the array has the same wafer structure as in Ref. 4. To remove the single mode yield issue caused by the back facet cleaving, the lasers are electrically divided into two sections isolated naturally by one slot: the front section includes a group of slots and the back section consists of a straight waveguide.…”

“…The designed laser array was fabricated using the similar process in Ref. 4. The total length of each laser in the fabricated array is around 400 μm integrated with a 190 μm long curved front SOA.…”