Dresden 2014 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HL: Fachverband Halbleiterphysik

HL 30: Poster: Quantum dots and wires: Preparation, characterization, optical properties and transport

HL 30.14: Poster

Monday, March 31, 2014, 17:00–20:00, P2

Capacitance-Voltage Spectroscopy of InAs Quantum Dots Under External Applied Strain — •Sascha René Valentin¹, Arne Ludwig¹, Dirk Reuter², and Andreas D. Wieck¹ — ¹Lehrstuhl für Angewandte Festkörperphysik, Ruhr Universität Bochum — ²Department Physik, Universität Paderborn

Self-assembled InAs quantumdots (QDs) are integrated in a variety of interesting optical and electronical devices and are also highly interesting from a fundamental point of view. Electric fields are often used to tune the optical and electronical properties of QDs. Recently it has been shown that external applied strain can reversibly shift the optical emission energy of QDs. Theoretical calculations indicate that the shift in the emission energy originates in the changed coulomb interaction between the charge carriers as well as in the shift of the energy levels themselves. In this project we want to measure the dependence of the interaction energies of the carriers on externally applied strain using capacitance voltage (CV) spectroscopy. In the device we present, a thin electrically contacted CV-membrane is bonded to a PMNPT-piezoelectric actuator. This allows to apply strain to the QDs and at the same time it enables electrical measurements on a QD ensemble.