Polarons Explain Luminescence Behavior of Colloidal Quantum Dots at Low Temperature
arXiv:1701.00930 · doi:10.1038/s41598-018-26678-w
Abstract
Luminescence properties of colloidal quantum dots have found applications in imaging, light-sources, and displays. Despite wide interest, several experimental observations from these quantum dots, such as the short lifetime on the scale of microseconds and a zero-longitudinal optical phonon line in low-temperature photoluminescence spectrum, remain unexplained by existing models. Here we propose a model including the effect of solid-state environment on luminescence by capturing coherent and incoherent interactions of band-edge exciton with phonon modes. Our model predicts the formation of dressed states by coupling of the exciton with a confined acoustic phonon mode, and explains the short lifetime and the presence of the zero-longitudinal optical phonon line in the spectrum. Accounting for the interaction of the exciton with bulk phonon modes, the model also explains the experimentally observed temperature-dependence of the photoluminescence decay dynamics and temperature-dependence of the photoluminescence spectrum.
arXiv comment5 figures and 4 supplementary figures; Pure dephasing of dressed dark state neglected, minor changes in figures, conclusions unchanged
References in corpus (16)
- Cavity quantum electrodynamics for superconducting electrical circuits: an architecture for quantum computation
- Quantum theory of collective strong coupling of molecular vibrations with a microcavity mode
- Frequency-dependent spontaneous emission rate from CdSe and CdTe nanocrystals: influence of dark states
- Statistical analysis of time-resolved emission from ensembles of semiconductor quantum dots: interpretation of exponential decay models
- Subnanosecond spectral diffusion measurement using photon correlation
- Epitaxial film growth and magnetic properties of Co_2FeSi
- Size dependent oscillator strength and quantum efficiency of CdSe quantum dots determined by controlling the local density of states
- Strongly nonexponential time-resolved fluorescence of quantum-dot ensembles in three-dimensional photonic crystals
- Phonon Mediated Off-Resonant Quantum Dot-Cavity Coupling
- Spin--flip Limited Exciton Dephasing in CdSe/ZnS Colloidal Quantum Dots
- Ultrafast supercontinuum spectroscopy of carrier multiplication and biexcitonic effects in excited states of PbS quantum dots
- Controlling the emission from semiconductor quantum dots using ultra-small tunable optical microcavities
- Quantitative analysis of quantum dot dynamics and emission spectra in cavity quantum electrodynamics
- Spectroscopy of 1.55 m PbS Quantum Dots on Si Photonic Crystal Cavities with a Fiber Taper Waveguide
- Fiber-based cryogenic and time-resolved spectroscopy of PbS quantum dots
- Overcoming Auger recombination in nanocrystal quantum dot laser using spontaneous emission enhancement