Use this URL to cite or link to this record in EThOS:
Title: Carbon nanotube solutions for ultrafast optical applications
Author: Hasan, T.
Awarding Body: University of Cambridge
Current Institution: University of Cambridge
Date of Award: 2009
Availability of Full Text:
Full text unavailable from EThOS.
Please contact the current institution’s library for further details.
This study is important in finding a suitable solvent-dispersant combination to stabilize dispersed single wall carbon nanotubes (SWNTs) at high (~0.16g/l) concentration. A method based on Photoluminescence excitation (PLE) spectroscopy is developed which can identify the presence of SWNT bundles regardless of the dielectric environment surrounding them. This method also enables correct interpretation of previously unassigned optical features in SWNT PLE maps. Enrichment of SWNTs by type and chiralities is investigated here as the next step towards the optimization of SWNT-polymer composites for optical applications. SWNT-polymer composites for sub-picosecond pulse generation at telecommunication C band (~1550nm) are prepared using SWNT-polycarbonate and SWNT-sodium carboxymethylcellulose composites. SWNTs of two different diameter ranges are used to demonstrate the importance of the correct band gap for wavelength specific operation. Passive mode-locking in a ring cavity using such saturable absorber SWNT-polymer composites exhibits stable operation. Up to ~170fs laser pulses at ~40MHz repetition rate for an output power of ~1mW are obtained at 1550nm. The cost, ease of fabrication and integration of these composites have huge commercial potential in low power ultrafast applications.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available