DocumentCode :
2072688
Title :
Electrorefraction in quantum dots: dependence on lateral size and shape
Author :
Rasanth, R.P. ; Haverkort, J.E.M. ; Wolter, J.H.
Author_Institution :
Dept. of Phys., Eindhoven Univ. of Technol., Netherlands
Volume :
1
fYear :
2003
fDate :
12-14 Aug. 2003
Firstpage :
126
Abstract :
Photonic switches require low loss polarization independent phase shifting elements. In a composite quantum well, a 0.46 mm phase shifter provides a π/4 phase shift by combining the Quantum Confined Stark Effect (QCSE) and carrier depletion effect. We investigate whether the discrete energy levels and the high peak absorption in quantum dots (QDs) provide an opportunity for increasing the electro-refraction. The electro-refraction in strained cylindrical InAs/GaAs QDs is explored using a numerical model based on the 4×4 Luttinger-Kohn Hamiltonian. The excitonic states are calculated by matrix diagonalization with plane-wave basis states. We observe that the QCSE sharply increases with the height of the QD and is also optimized for small radius QDs. The QCSE in pyramidal QDs is considerably larger than in squares or cylinders. We finally present large electro-refraction in, cone shaped pyramidal QDs.
Keywords :
III-V semiconductors; electro-optical effects; gallium arsenide; indium compounds; numerical analysis; quantum confined Stark effect; semiconductor quantum dots; 0.46 mm; InAs-GaAs; Luttinger-Kohn Hamiltonian; QCSE; QD; carrier depletion effect; composite quantum well; cone shaped pyramidal QD; discrete energy levels; electrorefraction; excitonic states; lateral shape; lateral size; low loss polarization independent phase shifting elements; matrix diagonalization; numerical model; peak absorption; phase shifter; photonic switches; plane wave basis states; quantum confined stark effect; quantum dots; strained cylindrical InAs/GaAs QD; Carrier confinement; Energy states; Optical losses; Phase shifters; Polarization; Potential well; Quantum dots; Shape; Stark effect; Switches;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Nanotechnology, 2003. IEEE-NANO 2003. 2003 Third IEEE Conference on
Print_ISBN :
0-7803-7976-4
Type :
conf
DOI :
10.1109/NANO.2003.1231731
Filename :
1231731
Link To Document :
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