Influence of applied electric field on the absorption coefficient and subband distances in asymmetri

• 作 者: 岑龙斌 沈波 秦志新 张国义
• 机 构: State Key Laboratory of Artificial Microstructure and Mesoscopic Physics,School of Physics,Peking Un
• 出 处: Chinese Physics B
• 发表日期: 2009年09期
• 关键词: asymmetrical modulator consistently spite operated excited realized symmetry Poi

The influence of applied electric fields on the absorption coefficient and subband distances in asymmetrical AlN/GaN coupled double quantum wells(CDQWs) has been investigated by solving Schrdinger and Poisson equations self-consistently.It is found that the absorption coefficient of the intersubband transition(ISBT) between the ground state and the third excited state(1odd 2even) can be equal to zero when the electric fields are applied in asymmetrical AlN/GaN CDQWs,which is related to applied electric fields induced symmetry recovery of these states.Meanwhile,the energy distances between 1odd 2even and 1even 2even subbands have different relationships from each other with the increase of applied electric fields due to the different polarization-induced potential drops between the left and the right wells.The results indicate that an electrical-optical modulator operated within the opto-communication wavelength range can be realized in spite of the strong polarization-induced electric fields in asymmetrical AlN/GaN CDQWs.

The influence of applied electric fields on the absorption coefficient and subband distances in asymmetrical AlN / GaN coupled double quantum wells (CDQWs) has been investigated by solving Schrödinger and Poisson equations self-consistently. It is found that the absorption coefficient of the intersubband transition (ISBT) between the ground state and the third excited state (1odd 2even) can be equal to zero when the electric fields are applied in asymmetrical AlN / GaN CDQWs, which is related to applied electric fields induced symmetry recovery of these states. , the energy distances between 1odd 2even and 1even 2even subbands have different relationships from each other with the increase applied electric fields due to the different polarization-induced potential drops between the left and the right well. These results indicate that an electrical-optical modulator operated within the opto-communication wavelength range can be realized in spite of the strong polarization-induced electr ic fields in asymmetrical AlN / GaN CDQWs.