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A GaAs-based epitaxially regrown photonic crystal surface-emitting laser is proposed and demonstrated at room temperature. The photonic crystal band-structure is mapped through the angular dependence of subthreshold electroluminescence, allowing the photonic crystal coupling coefficients to be determined.
We propose and demonstrate a technique for tailoring the emission bandwidth of /spl sim/1.3 /spl mu/m quantum dot superluminescent light-emitting diodes. A broadening of the emission is achieved by incorporating the InAs quantum dot layers in InGaAs quantum wells of different indium compositions. These structures exhibit a broader and flatter emission(More)
The combination of high-growth-temperature GaAs spacer layers and high-reflectivity (HR)-coated facets has been utilized to obtain low threshold currents and threshold current densities for 1.3-/spl mu/m multilayer InAs-GaAs quantum-dot lasers. A very low continuous-wave (CW) room-temperature threshold current of 1.5 mA and a threshold current density of(More)
The effects of modulation p-doping on 1.3-mum InGaAs-InAs quantum-dot (QD) lasers are systematically investigated using a series of wafers with doping levels from 0 to 18 acceptors per QD. Various characterization techniques for both laser diodes and surface-emitting light-emitting diode structures are employed. We report: 1) how the level of modulation(More)
Quantum dot (QD) superluminescent diodes (SLDs) exhibiting 8 mW and 95 nm full-width at half-maximum centered at 1270 nm are demonstrated with a flat-topped spectral profile. This is achieved using 3 times 2 dots in compositionally modulated wells technique. Furthermore, techniques for realization of high-power SLDs are also demonstrated. A continuous-wave(More)
E. Clarke, P. Howe, M. Taylor, P. Spencer, E. Harbord, R. Murray, S. Kadkhodazadeh, D. W. McComb, B. J. Stevens, and R. A. Hogg Department of Physics, Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2AZ, United Kingdom Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ, United Kingdom School of(More)
Key device requirements for maximising resolution in an optical coherence tomography system are discussed. The design and operating parameters of a multi-contact quantum dot superluminescent diode incorporating a number of features which inhibit lasing are described. Such devices allow the independent tuning of emission power and spectral shape; hence the(More)
We demonstrate a semiconductor PCSEL array that uniquely combines an in-plane waveguide structure with nano-scale patterned PCSEL elements. This novel geometry allows two-dimensional electronically controllable coherent coupling of remote vertically emitting lasers. Mutual coherence of the PCSEL elements is verified through the demonstration of a(More)
High pulse repetition rate (≥ 10 GHz) diode-pumped solid-state lasers, modelocked using semiconductor saturable absorber mirrors (SESAMs) are emerging as an enabling technology for high data rate coherent communication systems owing to their low noise and pulse-to-pulse optical phase-coherence. Quantum dot (QD) based SESAMs offer potential advantages to(More)
This paper details the development of broadband sources at 1050 nm for optical coherence tomography applications. A method for obtaining a broad and smooth emission and gain spectrum for 1050 nm quantum dot (QD) layers is presented. The design, fabrication, and operating characteristics of multicontact superluminescent diodes are then set out, and the(More)