Use this URL to cite or link to this record in EThOS:
Title: Monolithically integrated polarisation mode convertor with a semiconductor laser
Author: Naeem, Muhammad Azhar
ISNI:       0000 0004 2736 6328
Awarding Body: University of Glasgow
Current Institution: University of Glasgow
Date of Award: 2013
Availability of Full Text:
Access from EThOS:
Access from Institution:
In this thesis, the design, optimisation, fabrication and operation of waveguide based semiconductor lasers, integrated with polarisation mode convertors (PMCs), is described. Devices are fabricated in the GaAs/AlGaAs and InP/AlGaInAs material systems, using two types of structures; single PMC and back-to-back PMCs. The convertor designs are based upon air trenches, of sub-wavelength dimensions, being introduced into waveguide structures in order to achieve an asymmetric cross-sectional profile, resulting in wave-pate functionality. The GaAs/AlGaAs PMCs are fabricated using reactive ion etching (RIE), and the phenomena of RIE lag technique is also exploited for obtaining the required asymmetric waveguide profile in a single etch step. These are then integrated with semiconductor lasers. The InP/AlGaInAs PMCs are fabricated using a combination of RIE and inductively coupled plasma (ICP) etching and are integrated with semiconductor lasers and also differential phase shifter (DPS) sections to realise devices with active polarisation control. Integrated devices fabricated on InP/AlGaInAs material system with a semiconductor laser, a PMC followed by a DPS section yields ~40 % polarisation mode conversion whilst the DPS section is held at the transparency condition. Greater than 85 % polarisation mode conversion was also obtained with back to back PMCs, which was complement to the devices fabricated with a single PMC. Furthermore, a first active polarisation controller, monolithically integrated with a semiconductor laser is reported. High speed modulation of the integrated device with 300 Mbps is also demonstrated via current injection to the phase shifter section of the device.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: T Technology (General) ; TK Electrical engineering. Electronics Nuclear engineering