Temperature dependence of optical near-field energy transfer rate between two quantum dots in nanophotonic devices

摘要

We have obtained a simple numerical model that explains the temperature behavior of multi-quantum-dot (QD) nanophotonic devices whose operations are based on optical near-field (ONF) interactions between any two resonant QDs that are in thermal equilibrium. This model involves a set of coupled rate equations that govern the temporal behavior of the QDs' energy level occupancies. Under a certain operating condition, this simple model can substitute for the more complex density matrix (DM) approach in modeling the temperature dependence of the ONF energy transfer rate (R_(ONF)) between any two resonant QDs in thermal equilibrium. The same applies for modeling the system state-filling time ((tau)_(S)). Applying our simple model to a two-QD system, we have derived analytical formulas for the interdot and the intradot transfer rates at finite temperatures (T >= 0). Furthermore, by assuming a unidirectional energy transport operating condition, we have also derived an analytic formula for calculating (tau)_(S) for a two-QD system. To the best of our knowledge, this work is the first instance of reporting such analytic equations. Approximated values of (tau)_(S) obtained from our simple analytic equation are in reasonable agreements with those calculated by the DM approach.