Author Affiliations

D. M. Monro,^* J. A. Dallas,^* J. A. Nicholls,^* M. D. Cripps,^† and W. A. Crossland^§

^*School of Electronic and Electrical Engineering, University of Bath, Bath, BA2 7AY, England

^†Department of Electrical, Electronic and Information Engineering, City University, Northampton Square, London EC1V 0HB

^§Engineering Department, Cambridge University, Trumpington Street, Cambridge, CB2 1PZ

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