Polarisation independent refractive index change in InGaAs/InGaAsP tensile strained quantum well

The polarisation independent refractive index change in the tensile strained InGaAs/InGaAsP quantum well (QW) structure has been measured over the whole spectral range, i.e. near and below the bandgap energy. By inducing a 0.3% tensile strain in the InGaAs QW, the spectral profiles for the TE and TM modes are brought closer to each other, with the same refractive index change occurring at around 1.565 μm.