Uniaxially tensile strained Ge/SiGe coupled quantum wells

We propose and analyze the Ge/SGe coupled quantum wells (CQWs) with uniaxial tensile strain. A suspended micro bridge structure is employed to introduce the uniaxial tensile strain and the value of tensile strain can be tuned through the size and shape of the suspended region. The band dispersion and absorption spectrum of the strained Ge/SiGe CQWs are calculated for both 1E and TM polarizations by an 8 band kp model. By introducing 1% uniaxial tensile strain, the absorption band edge has a prominent red shift more than 100nm for both TE and TM polarizations. Under the influence of uniaxial tensile strain, the absorption of TE polarization is enhanced while the absorption of TM polarization is receded. The proposed uniaxially tensile srained Ge/SiGe CQWs scheme paves the way to efficient silicon based integrated devices.

Automated summary

The Ge/SGe coupled quantum wells with uniaxial tensile strain can be tuned through the size and shape of the suspended region, resulting in enhanced absorption for TE polarization and decreased absorption for TM polarization. This proposed scheme opens the way for efficient silicon-based integrated devices.