Tuning quantum-dot based photonic devices with liquid crystals.
Microdisks made from GaAs with embedded InAs quantum dots are immersed in the liquid crystal 4-cyano-4'-pentylbiphenyl (5CB). The quantum dots serve as emitters feeding the optical modes of the photonic cavity. By changing temperature, the liquid crystal undergoes a phase transition from the isotropic to the nematic state, which can be used as an effective tuning mechanism of the photonic modes of the cavity. In the nematic state, the uniaxial electrical anisotropy of the liquid crystal molecules can be exploited for orienting the material in an electric field, thus externally controlling the birefringence of the material. Using this effect, an electric field induced tuning of the modes is achieved. Numerical simulations using the finite-differences time-domain (FDTD) technique employing an anisotropic dielectric medium allow to understand the alignment of the liquid crystal molecules on the surface of the microdisk resonator.
Piegdon
Karoline A
KA
Physics Department and CeOPP, University of Paderborn, Warburger Strasse 100, 33098 Paderborn, Germany.
Declair
Stefan
S
Förstner
Jens
J
Meier
Torsten
T
Matthias
Heiner
H
Urbanski
Martin
M
Kitzerow
Heinz-S
HS
Reuter
Dirk
D
Wieck
Andreas D
AD
Lorke
Axel
A
Meier
Cedrik
C