SBIR Phase I: Novel Monolithically Integrated Wavelength-Range-Selectable and Widely-Wavelength-Tunable Semiconductor Lasers with High Functionalities

This Small Business Innovation Research (SBIR) Phase I project is focused on the technology development of a novel tunable laser and a novel wavelength selectable laser. Such lasers are central to next-generation optical networks and photonic technologies, including DWDM networks, all optical dynamic routing and packet switching networks, Optical CDMA networks, and analog photonics. Recently the company has developed a powerful integrated curved diffraction grating on InP chip with the highest spectral resolution and the smallest size, referred to as SCG. Applying to lasers, SCG allows the combination of the high performance of "external grating laser" with the advantages of integration. The project will focus on demonstrating the feasibility of the proposed SCG based lasers and developing a wavelength-range selectable narrowly-tunable SCG laser (WSNT-SCGL). These wavelength-selectable or tunable lasers will result in extended tunable laser capabilities not achievable currently such as wider tunability (e.g. >100nm), higher spectral purity (e.g. 50-60dB SMSR), narrower linewidth (e.g. 50mW), simpler control electronics, enhanced functionalities, and lower costs via monolithic integration. The proposed wavelength-selectable or widely-tunable SCG lasers involve a number of new technological approaches such as the high-resolution Integrated Curved Diffraction Grating, Cavity- Grating Frequency Offset detector, Matrix-Addressable Wavelength Tuner, and other integrated functionalities (e.g. widened gain section, integrated shutter/amplifier, integrated modulator etc). These are combined capabilities that can only be realized with chip-scale monolithic integrations, and are not available currently. For optical networks, currently one has to use 40x fixed wavelength DFB lasers or 10x narrowly-tunable DFB lasers to cover the 40 DWDM ITU Channels. These lasers can be replaced by a single WSNT-SGC laser. Thus, the WSNT-SCG laser will reduce the DWDM laser inventory by 10- 40x. The company's widely tunable lasers WT-SCG, on the other hand, will bring substantially lower power consumption and simpler control electronics than current tunable lasers, and could be engineered to give higher output and higher spectral purity. The potentially new capabilities of SCG lasers will open up many application areas including: (1) DWDM/CWDM/OCDMA Networks; (2) WDM On Chips; (3) Instrumentations, and (4) Analog/RF Photonics. Applications to these areas require lambda-selectable or tunable lasers with higher output, higher SMSR, wider lambda-tunability, narrower linewidth, and lower cost than currently available.