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We demonstrate radio-frequency tuning of the energy of individual CdTe/ZnTe quantum dots (QDs) by Surface Acoustic Waves (SAWs). Despite the very weak piezoelectric coefficient of ZnTe, SAW in the GHz range can be launched on a ZnTe surface using interdigitated transducers deposited on a c-axis oriented ZnO layer grown on ZnTe containing CdTe QDs. The photoluminescence (PL) of individual QDs is used as a nanometer-scale sensor of the acoustic strain field. The energy of QDs is modulated by SAW in the GHz range and leads to the characteristic broadening of time-integrated PL spectra. The dynamic modulation of the QD PL energy can also be detected in the time domain using phase-locked time domain spectroscopy. This technique is, in particular, used for monitoring complex local acoustic fields resulting from the superposition of two or more SAW pulses in a cavity. Under a magnetic field, the dynamic spectral tuning of a single QD by SAW can be used to generate single photons with alternating circular polarization controlled in the GHz range. [ABSTRACT FROM AUTHOR]

The optimal design of the doping level in a lateral spin-injection-detection device is discussed based on two-dimensional self-consistent simulations. The optimization is done in order to achieve an optimal tunnel barrier resistance and the doping of the spin-transport region is engineered to obtain optimal current distribution.

We report on the properties of 10 nm thick Co50Fe50 interdigitated electrodes deposited on lead zirconate titanate (PZT) substrates to achieve low power dynamic tuning of magnetic properties. The actuation of this combination relies on magnetoelectric coupling through the shear mode deformation of the PZT: numerical simulations confirmed that both uniaxial tensile and compressive strain can be achieved either by applying a bias voltage on the appropriate set of electrodes or by reversing the polarity of the bias voltage. Reversible electric field induced changes in the coercive field of more than 10% and a 0.08% change in the resistance were obtained for an applied electrical field of 5 kV/cm. [ABSTRACT FROM AUTHOR]

The properties of 10 nm thick [Co.sub.50][Fe.sub.50] interdigited electrodes deposited on lead zirconate titanate (PZT) substrates are described in order to achieve low power dynamic tuning of magnetic properties. The reversible electric field induced changes in the coercive field of more than 10% and a 0.08% change in the resistance are obtained for an applied electrical field of 5kV/cm.