Relaxation time distribution of distant-pair recombination: Application to QFRS of PL in a-Si:H.

The distribution function of relaxation time of distant-pair (DP), or nongeminate recombination is derived in an analytic form from the existing theories of DP recombination to analyse the data of quadrature frequency resolved spectroscopy (QFRS) of photoluminescence (PL) in a-Si:H with the competing recombination model. The distribution function has a single parameter of metastable carrier density n and yields too narrow QFRS spectrum to fit the experimental data. This is improved with introducing the fluctuation Δ of the electron localisation radius ae. The devised formula is demonstrated to predict the dependence of the DP recombination on the photogeneration rate and the defect density in the QFRS data of the high-quality and defective a-Si:H. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]