Quantum-confined Stark effect in partially strained quantum wells

Summary form only given. In a uniformly strained quantum well (QW), the valence band potential profiles for the heavyhole (HH) and the light-hole (LH) are square wells with equal width. Because the HH has a larger effective mass along axis of the growth direction, it experiences a stronger quantum confined Stark effect (QCSE). This property is undesirable in optical communication applications where polarization-preserving optical fiber is not used. In this paper, we present a novel partially strained QW in which the rate of the QCSE can be separately engineered. We show experimentally and theoretically that in certain cases the HH QCSE is enhanced, while in other cases the LH QCSE is enhanced. It is also possible to achieve bias independent HH and LH degeneracy. We have inserted thin layers of highly strained GaAs in an unstrained InGaAs QW grown on InP.