Optical quantum yield in plasmonic nanowaveguide

Splitting of the Effective Rabi Frequencies for the Coherent Plasmonic Fields in the Semiconductor Quantum Dot–Metal Nanospheres Hybrids

Splitting of the effective Rabi frequencies for plasmonic fields when the interaction occurs between semiconductor quantum dot and three metallic nanospheres in the presence of three electromagnetic fields is examined. We study theoretically the role of the dipole–dipole interactions in creating many Multipoles. Then, we split the effective Rabi frequencies into three parts according to the quantitative Multipoles of the plasmonic fields. The density matrix equations are derived for the description of the optical properties of the SQD-MNPs nanosystem. We investigate the influence of each part of the effective Rabi frequencies and compare them with each other individually. The three parts of the effective Rabi frequency for the probe field are affected by changing the angles, the strong probe field and other parameters for the hybrid system.

Tunable Narrowband Silicon-Based Thermal Emitter with Excellent High-Temperature Stability Fabricated by Lithography-Free Methods

Thermal emitters with properties of wavelength-selective and narrowband have been highly sought after for a variety of potential applications due to their high energy efficiency in the mid-infrared spectral range. In this study, we theoretically and experimentally demonstrate the tunable narrowband thermal emitter based on fully planar Si-W-SiN/SiNO multilayer, which is realized by the excitation of Tamm plasmon polaritons between a W layer and a SiN/SiNO-distributed Bragg reflector. In conjunction with electromagnetic simulations by the FDTD method, the optimum structure design of the emitter is implemented by 2.5 periods of DBR structure, and the corresponding emitter exhibits the nearly perfect narrowband absorption performance at the resonance wavelength and suppressed absorption performance in long wave range. Additionally, the narrowband absorption peak is insensitive to polarization mode and has a considerable angular tolerance of incident light. Furthermore, the actual high-quality Si-W-SiN/SiNO emitters are fabricated through lithography-free methods including magnetron sputtering and PECVD technology. The experimental absorption spectra of optimized emitters are found to be in good agreement with the simulated absorption spectra, showing the tunable narrowband absorption with all peak values of over 95%. Remarkably, the fabricated Si-W-SiN/SiNO emitter presents excellent high-temperature stability for several heating/cooling cycles confirmed up to 1200 K in Ar ambient. This easy-to-fabricate and tunable narrowband refractory emitter paves the way for practical designs in various photonic and thermal applications, such as thermophotovoltaic and IR radiative heaters.