Biography

Further details can be found on my personal web page.

A full list of publications, conference presentations, and patents can be found here.

Research Interests

Stephen's primary research interests lie in the area of semiconductor laser physics with a particular onus on optimising laser performance. He has produced >150 journal papers and conference proceedings in this area including several invited papers. Stephen has recently expanded his interests into photonic sensors based on both III-V and Si technologies. Recent topics include:

• semiconductor lasers for temperature insensitive operation (quantum dots, dilute-nitrides etc)
• widely tunable lasers
• vertical cavity surface emitting lasers and LEDs for plastic fibre systems
• semiconductor lasers for optical pumping (EDFA, Raman) and printing and data storage applications
• using photonic devices to sense chemical and biological samples (liquids and gases)

Information about currently available PhD projects can be found here

Research Collaborations

Current and previous collaborators include:
Commercial:

• JDS
• Bookham
• Infineon
• Fujitsu
• Agilent
• CIP
• Philips
• Cedova
• LSA

Academic:

• Arizona State University
• Philips Universitaet Marburg
• Universitaet Wuerzburg
• Okayama University
• Stanford University
• Tampere University of Technology
• Imperial College London
• Sheffield University
• Tyndall Institute, Cork
• UC San Diego

Publications

Recent publications

J1.            “Temperature dependence and physical properties of Ga(NAsP) semiconductor lasers”, J. A. Chamings, A. R. Adams, S. J. Sweeney, B. Kunert, K. Volz and W. Stolz, Appl. Phys. Lett., 93 pp101108-101110 (2008).

 J2.            “Physical properties and Efficiency of GaNP Light Emitting Diodes”, J. Chamings, S. Ahmed, S. J. Sweeney, V. A. Odnoblyudov and C. W. Tu, Appl. Phys. Lett. 92, pp021101-021103 (2008).

 J3.            “Temperature insensitive quantum dot lasers: are we really there yet?”, N. F. Masse, I. P. Marko, A. R. Adams and S. J. Sweeney, Jour. Mat. Sci.: Mat. In Electronics, 957, pp4522-4526 (2008).

 J4.            “Optimisation of Distributed Feedback Lasers for Biosensing applications”, J. Coote, S. R. Reddy and S. J. Sweeney, IET Optoelectronics, 1, pp266-271 (2007).

 J5.            “Temperature and pressure dependence of the recombination processes in 1.5µm InAs/InP (311)B quantum dot lasers”, N. F. Massé, E. Homeyer,A. R. Adams, S. J. Sweeney,  O. Dehaese, R. Piron, F. Grillot, S. Loualiche, Appl. Phys. Lett. 91, pp131113-131115 (2007).

 J6.             “Microscopic electroabsorption lineshape analysis for GaAsSb/GaAs heterostructures”, C. Bückers, G. Blume, A. Thränhardt, C. Schlichenmaier, P. J. Klar, G. Weiser, S. W. Koch, J. Hader, J. V. Moloney, T. J. C. Hosea, S. J. Sweeney, S. R. Johnson and Y.-H. Zhang, Jour. Appl. Phys., 101, pp033118-033125 (2007).

 J7.            “Experimental determination of the band gap dependence of Auger recombination in InGaAs/InP multiple-quantum well lasers at room temperature”, N. F. Masse, A. R. Adams and S. J. Sweeney, Appl. Phys. Lett., 90, pp161113-161115 (2007).

 J8.            “Long wavelength bulk GaInNAs p-i-n photodiodes lattice-matched to GaAs”, J. S. Ng, W. M. Soong, M. Steer, M. Hopkinson, J. P. R. David, J. Chamings, S. J. Sweeney and A. R. Adams, Jour. Appl. Phys., 101, pp064506-064511 (2007).

 J9.            “High pressure studies of mid-infrared type-II “W” diode lasers at cryogenic temperatures”, K. O’Brien, A. R. Adams, S. J. Sweeney, S. R. Jin, C. N. Ahmad, B. N. Murdin, C. L. Canedy, I. Vurgaftman and J. R. Meyer, Physica Status Solidi (b), 244, pp224-228 (2007).

 J10.        “Band gap dependence of the recombination processes in InAs/GaAs quantum dots studied using hydrostatic pressure”, I. P. Marko, A. R. Adams, S. J. Sweeney, N. F. Masse, R. Krebs, J. P. Reithmaier, A. Forchel, D. J. Mowbray, M. S. Skolnick, H. Y. Liu, K. M. Groom, N. Hatori and M. Sugawara,Physica Status Solidi (b), 244, pp82-86 (2007).

 J11.        “Temperature and Pressure Dependence of Carrier Recombination Processes in GaAsSb/GaAs Quantum Well Lasers”, K. Hild, S. J. Sweeney, I. P. Marko, S. R. Jin, S. R. Johnson, S. A. Chaparro, S. Yu and Y.-H. Zhang, Physica Status Solidi (b), 244, pp197-202 (2007).

 J12.        “The temperature and pressure dependence of carrier recombination processes in 1.3mm and 1.5mm GaInNAs lasers”, D. G. McConville, S. J. Sweeney, A. R. Adams, S. Tomic and H. Riechert,Physica Status Solidi (b), 244, pp208-212 (2007).

 J13.        “Carrier recombination mechanisms in mid-infrared GaInAsSb quantum well lasers”, K. O’Brien, S. J. Sweeney, A. R. Adams, S. R. Jin, C. N. Ahmad, B. N. Murdin, A. Salhi, Y. Rouillard and A. Joullie,Physica Status Solidi (b), 244, pp203-207 (2007).

 J14.        “Carrier recombination in 1.3mm GaAsSb/GaAs Quantum Well Lasers”, K. Hild, S. J. Sweeney, S. Wright, D. A. Lock, S. R. Jin, I. P. Marko, S. R. Johnson, S. A. Chaparro, S.-Q. Yu and Y.-H. Zhang, Applied Physics Letters 89, pp173509-173511 (2006).

 J15.        “Temperature dependence of the gain in p-doped and intrinsic 1.3mm InAs/GaAs quantum dot lasers”, N. F. Masse, S. J. Sweeney, I. P. Marko, A. R. Adams, N. Hatori and M. Sugawara, Applied Physics Letters 89, pp1191118-1191120 (2006) [Also selected by the editor for publication in the Virtual Journal of Nanoscale Science and Technology, 27^th November 2006 edition, see www.vjnano.org ].

 J16.        “Spectroscopy of GaAs/AlGaAs quantum-cascade lasers using hydrostatic pressure”, S. R. Jin, C. N. Ahmad, S. J. Sweeney, A. R. Adams, B. N. Murdin, H. Page, X. Marcadet, C. Sitori and S. Tomic, Applied Physics Letters, 89, p221105-221107 (2006).

 J17.        “Recombination processes in mid-infrared InGaAsSb diode lasers emitting at 2.37mm”, K. O’Brien, S. J. Sweeney, A. R. Adams, B. N. Murdin, A. Salhi, Y. Rouillard and A. Joullie, Appl. Phys. Lett., 89, pp051104-051106 (2006).

Teaching

Level 0 Foundation Year Tutorials
Level 1 Principles of Physics (1PP)
Level 1 Electronics (1EL)
Level 1 Physics Laboratories (1LAB)
Level 2 Solid State / Thermal Physics Laboratories (2SS/TP)
Level 3 Physics in Education (3PIE) [assessor]
Level M Photonics and Nanotechnology (3PNT)
Level D LabView

Departmental Duties

• Chair of Physics Department Board of Studies (2009-)
• Chair of Physics Department BoS sub-committee (2009-)
• MPhys/BSc Physics Programme Coordinator (2009-)
• Physics with Foundation Year Co-ordinator (2003-2006)
• Physics Schools Liaison Officer (2004-2008)
• Physics Marketing group (2006-)
• Physics MPhys research placements co-ordinator (2006-)
• ATI Postgraduate Admissions Tutor (2002-2008)
• FEPS PG Research committee (2002-2008)

Research Grants

Stephen has attracted over £2M of research funding from sources including EPSRC, The Nuffield Foundation, the DTI, TSB and other commercial organisations.

Books

1. "Optoelectronic Devices and Materials", S. J. Sweeney and A. R. Adams, Chapter in Handbook of Electronic Materials, Springer-Verlag, 2006.
2. "Band-structure and high pressure measurements", B. N. Murdin, A. R. Adams and S. J. Sweeney, in Mid-IR Materials and Devices, Springer, 2006.