Announcing the Final Examination of Srinivas Varma Pericherla for the degree of Doctor of Philosophy
Semiconductor lasers are considered essential for the advancement in the field of photonics where compact and energy-efficient lasers are necessary. Advancements in integrated photonic technologies will help push the performance of semiconductor lasers in the coming years and expand the technology to several other applications. Semiconductor lasers offer several key features such as high energy efficiency, mass production, availability at a myriad of wavelengths, and high integration capabilities. However, limitations in noise performance, pulse energy, and duration hold back semiconductor lasers from being utilized to their full potential. This dissertation reviews the utilization and development of external techniques that enable semiconductor mode-locked lasers to be used in multi-photon imaging and microwave photonic applications. We first review a two-color external cavity mode-locked laser system operating at wavelengths 834 nm and 974 nm that can generate synchronized picosecond pulses with peak powers exceeding 80 W and 100 W respectively. We verify the feasibility of this system to induce non-linear processes by demonstrating two-photon excitation in commercially available dyes. Next, we introduce the concepts of optical injection locking and discuss the development of a multi-tone optical self-injection locking technique to improve the noise performance and optical linewidth of a chip-scale InP based mode-locked laser. We utilize a Fabry-Perot etalon as the optical comb filter, which also serves to suppress the super-mode noise that arises from external cavity feedback. In addition to this, we also implement a coupled opto-electronic loop that is referenced to an external RF source demonstrating exceptional timing stability. This approach along with the usage of fully integrated and ultra-compact components in subsequent versions has the potential to realize compact frequency comb lasers for microwave photonic and other practical applications
Committee in Charge:
Peter J. Delfyett, Chair, CREOL, ECE
Murat Yuksel, ECE
Sasan Fathpour, CREOL, ECE
Kenle Chen, ECE
Kyu Young Han, CREOL