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arXiv · 1507.05465

p-State Luminescence in CdSe Nanoplatelets: The Role of Lateral Confinement and an LO Phonon Bottleneck

Alexander W. Achtstein·Riccardo Scott·Sebastian Kickhöfel·Stefan T. Jagsch·Sotirios Christodoulou·Anatol V. Prudnikau·Artsiom Antanovich·Mikhail Artemyev·Iwan Moreels·Andrei Schliwa·Ulrike Woggon
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Abstract

We report excited state emission from p-states at excitation fluences well below ground state saturation in CdSe nanoplatelets. Size dependent exciton ground state-excited state energies and dynamics are determined by three independent methods, time-resolved photoluminescence (PL), time-integrated PL and Hartree renormalized k$\cdot$p calculations -- all in very good agreement. The ground state-excited state energy spacing strongly increases with the lateral platelet quantization. Our results suggest that the PL decay of CdSe platelets is governed by an LO-phonon bottleneck, related to the reported low exciton phonon coupling in CdSe platelets and only observable due to the very large oscillator strength and energy spacing of both states.

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Alexander W. Achtstein, Riccardo Scott, Sebastian Kickhöfel, Stefan T. Jagsch, Sotirios Christodoulou, Anatol V. Prudnikau, Artsiom Antanovich, Mikhail Artemyev, Iwan Moreels, Andrei Schliwa, Ulrike Woggon. 2015-07-20. p-State Luminescence in CdSe Nanoplatelets: The Role of Lateral Confinement and an LO Phonon Bottleneck. https://doi.org/10.1103/physrevlett.116.116802

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