Bałakier, Katarzyna;
(2016)
High-purity Tuneable Photonic-integrated Millimetre-wave and Terahertz Sources.
Doctoral thesis (Ph.D), UCL (University College London).
Preview |
Text
PhD Balakier_e-thesis.pdf - Accepted Version Download (126MB) | Preview |
Abstract
This research work focuses on the design and characterisation of indium phosphide photonic integrated circuits for continuous-wave, high-purity millimetre-wave (mm-wave) and terahertz (THz) signal generation. Each source investigated in this work is based on a photonic oscillator (PO) consisting of monolithically integrated semiconductor lasers, and a broad bandwidth photodiode to convert the heterodyne signal from the optical to the electrical domain. The resulting photocurrent contains a component at the desired mm-wave or THz frequency corresponding to the frequency difference between the two lasers. In this thesis, the specifics of three POs are discussed, and dedicated laser phase-locking solutions are investigated and implemented, resulting in a high-purity mm-wave photonic synthesiser being realised and a novel THz PO being proposed and constructed. The former is a compact mm-wave photonic synthesiser consisting of two lasers monolithically integrated with fast photodiodes. High-quality, low-phase-noise signal above 100 GHz is demonstrated through optical injection locking, allowing the synthesised signal to be finely tuned across a 30 GHz span. Furthermore, the phase stabilisation scheme based on optical phase lock loop (OPLL) was constructed and discussed. The latter is a broadly tuneable THz signal generator based on a photonic integrated circuit developed using a generic fabrication foundry approach. The implementation of the photonic chip with twin OPLL enables the two optical lines to combine at the output and create a high-purity, continuously tuneable optical heterodyne signal, which can be data modulated. Furthermore, OPLL operation principles are investigated, leading to the establishment of design guidelines and a definition of the trade-offs present in OPLLs. The integrated POs discussed in this work could be an answer to the need for tuneable, portable, cost- and energy-efficient THz sources that can operate at room temperature. Photonic-enabled emitters have the potential to overcome the limitations of conventional emitters, thereby accelerating the development of coherent THz technology and its applications in spectroscopy, sensing, security and short-range broadband wireless communications.
Type: | Thesis (Doctoral) |
---|---|
Qualification: | Ph.D |
Title: | High-purity Tuneable Photonic-integrated Millimetre-wave and Terahertz Sources |
Event: | UCL (University College London) |
Open access status: | An open access version is available from UCL Discovery |
Language: | English |
UCL classification: | UCL UCL > Provost and Vice Provost Offices UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Electronic and Electrical Eng |
URI: | https://discovery.ucl.ac.uk/id/eprint/1476759 |
Archive Staff Only
View Item |