Jean-Louis Gentner

Two-dimensional photonic crystal coupled-defect laser diode

We demonstrate a two-dimensional photonic crystal defect laser diode based on a coupled cavity waveguide. The laser cavity is formed by 40 coupled hexagonal defect microcavities in a triangular lattice of air cylinders, which are etched into an InGaAsP/InP laser structure. The coupling of the individual cavity modes creates minibands within the photonic band gap. Stable single-mode lasing occurs on the first miniband mode with the lowest group velocity with side mode suppression greater than 40 dB. The lasers emit up to 2.6 mW at a 1.53 μm wavelength under continuous-wave operation at room temperature.

Total in situ etching and regrowth in an MBE system: application to buried heterostructure lasers

A new chlorine-based chemical beam etching technique (CBET) has been combined with molecular beam epitaxy (MBE) technology to prepare InP-InGaAsP buried heterostructures in a total in situ etching and regrowth process for the first time. This novel processing technology, combining two techniques in the same MBE growth chamber, is very attractive for the realization of high-performance discrete or integrated optoelectronic devices. The different aspects of the etching process optimization are reviewed in the case of InP-InGaAsP heterostructures, and a first application to buried heterostructure laser fabrication is presented. The results obtained for buried ridge stripe (BRS) lasers are very promising and compare favorably to the state-of-the-art lasers. This first device application passes a milestone in the development of this new technology and demonstrates its potential for further applications to the fabrication of optoelectronic devices.

Transmission characteristics of 1.3 /spl mu/m Fabry-Perot laser diodes integrated with spot size converter for 2.5 Gbit/s applications

This article demonstrates the application of highly efficient Fabry-Perot lasers to intra-office STM-16 fiber communication systems at the wavelength of 1.3 /spl mu/m. Low power penalty of 0.05 dB through a 12 ps/nm fiber was measured at 25/spl deg/C and 85/spl deg/C. A low coupling loss of 1 dB of a laser to a cleaved SMF fiber is achieved. This device consists of an active stripe followed by a passive intracavity spot size converter. Subsequently, this paper demonstrates the feasibility of non-perturbing intracavity tapers through the application of selective area growth and their applicability to short haul optical systems.

High dynamic solutions for short-wavelength infrared imaging based on InGaAs

Short-wavelength infrared image sensors based on p-i-n photodiode arrays present a tremendous interest in applications such as passive and active imagery for laser detection/warning, hot spot or detection for lasers sensors, enhanced vision systems or low light level sensors. The capability to work at room temperature with dark current equivalent to silicon-based devices is another motivation for the fast development of this technology. This paper presents several modules and camera based on InGaAs photodiode arrays from the III-VLab. First, we describe the electro-optics performance in terms of dark signal, sensitivity, and particularly the visible extension capability. We also present a nucless logarithmic sensor based on a 1/2 video graphics array (VGA) format at a pitch of 25 μm initially designed for visible CMOS camera chip. We will also present the next generation of focal plane arrays based on a VGA format of 640×512 pixels with a pitch of 15 μm. This array will be associated to a CTIA readout circuit and also to an innovative CMOS logarithmic wide dynamic range ROIC, developed by New Imaging Technologies. This VGA logarithmic device developed for automotive safety will involve visible extension capability in a European project named 2Wide_sense.

Monolithically integrated tunable laterally-coupled distributed feedback lasers with self-aligned Ti/Pt/Au ohmic contacts

A new method for fabrication of tunable InGaAsP-InP single-mode lasers without epitaxial overgrowth is reported. These devices show the advantage of a considerably simplified fabrication process compared to conventional tunable laser types. The lasers comprise an active Bragg reflector integrated with an uncorrugated separately pumped gain region. By adjusting the current through the Bragg reflector, the wavelength can be tuned between 1590.8 and 1595.2 nm.

Low threshold current BH lasers fabricated by UHV chemical beam etching and GSMBE regrowth

A new chlorine-based chemical beam etching technique (CBET) compatible with MBE or CBE technology has been introduced recently. The process sequence combining these two techniques in the same MBE growth chamber is very attractive for the realisation of high performance discrete or integrated optoelectronic devices. In this paper, we present for the first time results on devices fabricated using this new processing technique. Fabry-Perot type 1.3 and 1.48 /spl mu/m Buried Heterostructure lasers with low threshold current values have been obtained. Well defined mesa profiles and excellent regrowth morphologies have been obtained. The effect of interface contamination has been pointed out, in particular for the case of silicon for which a direct effect on laser results has been shown.