Strain-induced tuning of the emission wavelength of high quality GaAs/AlGaAs quantum dots in the spectral range of the 87Rb D2 lines

Reversible biaxial strains are used for tuning the emission wavelengths of high quality GaAs/AlGaAs quantum dots (QDs) in the spectral range of the 87Rb D2 lines. The strain is transferred by integrating free standing (Al)GaAs nanomembranes, containing QDs, onto piezoelectric actuators. Narrow excitonic emission lines as sharp as 25 μeV are shown, and a tuning range larger than 5 nm is demonstrated. This range corresponds to an induced anisotropic biaxial strain of the order of 0.15%, as evaluated from the shift in the emission of the GaAs from the nanomembranes. The presented on-chip technology is potentially interesting for future quantum memories based on hybrid semiconductor-atomic interfaces.