Theoretical study of amplified spontaneous emission intensity and bandwidth reduction in polymer

• 来源期刊: 中国物理B（英文版）
• 关键词: amplified spontaneous emission bandwidth reduction polymers gain coefficient
• 年，卷（期）: 2015,（4）
• 页码范围: 043201-1-043201-14
• 页数: 1页
• 语种: 英文
• DOI: 10.1088/1674-1056/24/4/043201

摘要

Amplified spontaneous emission (ASE), including intensity and bandwidth, in a typical example of BuEH-PPV is calculated. For this purpose, the intensity rate equation is used to explain the reported experimental measurements of a BuEH-PPV sample pumped at different pump intensities from Ip=0.61 MW/cm2 to 5.2 MW/cm2. Both homogeneously and inhomogeneously broadened transition lines along with a model based on the geometrically dependent gain coefficient (GDGC) are examined and it is confirmed that for the reported measurements the homogeneously broadened line is respon-sible for the light–matter interaction. The calculation explains the frequency spectrum of the ASE output intensity extracted from the sample at different pump intensities, unsaturated and saturated gain coefficients, and ASE bandwidth reduction along the propagation direction. Both analytical and numerical calculations for verifying the GDGC model are presented in this paper. Although the introduced model has shown its potential for explaining the ASE behavior in a specific sample it can be universally used for the ASE study in different active media.