2024.2.2 由硕士研究生朱柏林完成的研究论文”Enhancing the Light Emission Efficiency of LEDs Based on Array of Ag Nanohollow Cylinders and SPR Theory”被《Optical Materials》录用！祝贺！

Abstract：The internal spontaneous emission and external light extraction efficiency have been key issues in the research on LEDs incorporating metal nanoparticles, particularly in terms of transmittance, which presents a series of challenges and less-than-satisfactory outcomes. In this study, we address this issue by proposing a new approach that combines periodic structures with metal surface plasmons. Specifically, we embed an array of Ag nanohollow cylinders above the quantum wells of the LED structure and investigate its impact on the light emission characteristics using the finite-difference time-domain (FDTD) method. By varying the height and radius ratio of the hollow cylinders, the internal spontaneous emission and external light extraction efficiency of the LED can be significantly enhanced. At h = 12 nm, r/R = 1:3, the internal spontaneous emission rate is enhanced by a factor of 3.64. Under the condition of r/R = 1:3, the internal quantum efficiency reaches 90% for h values of 3 nm, 6 nm, 9 nm, 12 nm, and 15 nm. The transmittance increases from 0.26 to 0.44 at h = 3 nm, r/R = 1:3, and the enhancement factor of light extraction efficiency also reaches 1.73. These research findings reveal that embedding a nano Ag hollow cylinder array structure above the active layer can significantly enhance the light emission efficiency of LEDs. The introduction of this structure effectively utilizes the surface plasmon resonance effects of metal nanoparticles and their coupling with the active layer. This provides an important theoretical reference for further improvement and optimization of metal nanostructure designs.

2024.4.25 由硕士研究生邓春兰完成的研究论文”Performance of nanoparticle-enhanced thin-film solar cell with near-perfect absorption”被《Physica B: Condensed Matter》录用！祝贺！

Abstract：This study proposes a thin-film solar cell composed of periodic plasmonic titanium nanoparticles (Ti NPs) and indium phosphide (InP) thin films. By adjusting the size and position of plasma Ti NPs and combining with the transparent conductive layer ITO and anti-reflection layer SiO2, the parameters of InP thin film solar cells can be improved. The experimental results show that the average absorption rate reaches 96% in the wavelength range of 350-850 nm. The absorption rate reached 99.9% in multiple wavelength ranges. This study has successfully increased the short circuit current to 31.996mA/cm^2, power conversion efficiency (PCE) to 29.634% and open circuit voltage to 1.053V of InP thin film solar cells.

2023.12.25 由硕士研究生潘哲完成的研究论文”Broadband THz Graphene Absorber with Graphene and Sensing of Trimethylglycine Concentration”被《Physica Scripta》录用！祝贺！

Abstract：This paper proposes a tunable broadband terahertz absorber based on metamaterial graphene. The absorber consists of a monolayer of graphene, a dielectric layer, and a metal reflection backing. By adjusting the applied bias voltage, the unique properties of graphene are utilized to control its Fermi level. Simulation results indicate that the absorber has an absorption rate exceeding 70% between 4.2-4.8 THz, with a maximum absorption rate reaching 99.99%, and a sensitivity of 740 GHz/RIU. Compared to similar studies, this structure has significant advantages in sensitivity. Due to the symmetry of the unit structure, the absorber is insensitive to the incident angle. We applied the absorber to trimethylglycine concentration. Experimental results show that the designed absorber can accurately identify the concentration of trimethylglycine solution, detecting concentrations as low as 0.5%.