Dresden 2017 – wissenschaftliches Programm
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HL: Fachverband Halbleiterphysik
HL 33: Quantum Dots: Optical Properties I
HL 33.6: Vortrag
Dienstag, 21. März 2017, 11:30–11:45, POT 81
Ultrafast electric control of a quantum dot exciton — •Amlan Mukherjee1,2,3, Alex Widhalm1,3, Nandlal Sharma1,3, Andreas Thiede2,3, Dirk Reuter1,3, and Artur Zrenner1,3 — 1Department Physik, Universität Paderborn, Paderborn, Germany — 2Höchstfrequenzelektronik, Universität Paderborn, Paderborn, Germany — 3Center for Optoelectronics and Photonics Paderborn (CeOPP), Universität Paderborn, Paderborn, Germany
The excellent optical properties of single InGaAs QDs combined with ultrafast electric control allow for the realisation of new coherent optoelectronic functionalities. Universal coherent control can be achieved by combining the control of occupancy using optical pulses with phase control using electric pulses within the dephasing time of the ground state QD exciton. To implement fast electric phase control, we have designed a SiGe:C hetero-bipolar electronic circuit for the generation of ultrafast electric signals, which act as phase gates for a single QD. Our current circuit design generates rise times below 15 ps and it is fully operational at liquid Helium temperatures. In Ramsey experiments we demonstrate a coherent electric phase manipulation over up to 20π and the realisation of a π phase change within 35 ps. Also, such ultrafast electrical pulses can be used in combination with cw excitaion to perform an adiabatic rapid passage for robust exciton generation. We report results from our attempts to perform the electrically chirped excitation of an exciton.