title: Surface plasmon coupling with radiating dipole for enhancing the emission efficiency of a light-emitting diode.
abstract: The experimental demonstrations of light-emitting diode (LED) fabrication with surface plasmon (SP) coupling with the radiating dipoles in its quantum wells are first reviewed. The SP coupling with a radiating dipole can create an alternative emission channel through SP radiation for enhancing the effective internal quantum efficiency when the intrinsic non-radiative recombination rate is high, reducing the external quantum efficiency droop effect at high current injection levels, and producing partially polarized LED output by inducing polarization-sensitive SP for coupling. Then, we report the theoretical and numerical study results of SP-dipole coupling based on a simple coupling model between a radiating dipole and the SP induced on a nearby Ag nanoparticle (NP). To include the dipole strength variation effect caused by the field distribution built in the coupling system (the feedback effect), the radiating dipole is represented by a saturable two-level system. The spectral and dipole-NP distance dependencies of dipole strength variation and total radiated power enhancement of the coupling system are demonstrated and interpreted. The results show that the dipole-SP coupling can enhance the total radiated power. The enhancement is particularly effective when the feedback effect is included and hence the dipole strength is increased.
authors: Institute of Photonics and Optoelectronics, and Department of Electrical Engineering, National Taiwan University, 1 Roosevelt Road, Section 4, Taipei, 10617 Taiwan.
authors: Yang
authors: Y
authors: Kuo
authors: Shao-Ying
authors: SY
authors: Ting
authors: Che-Hao
authors: CH
authors: Liao
authors: Jeng-Jie
authors: JJ
authors: Huang
authors: Chih-Yen
authors: CY
authors: Chen
authors: Chieh
authors: C
authors: Hsieh
authors: Yen-Cheng
authors: YC
authors: Lu
authors: Cheng-Yen
authors: CY
authors: Chen
authors: Kun-Ching
authors: KC
authors: Shen
authors: Chih-Feng
authors: CF
authors: Lu
authors: Dong-Ming
authors: DM
authors: Yeh
authors: Jyh-Yang
authors: JY
authors: Wang
authors: Wen-Hung
authors: WH
authors: Chuang
authors: Yean-Woei
authors: YW
authors: Kiang
authors: C C
authors: CC
authors: Yang