Electro-optic and electro-absorption characterization of InAs quantum dot waveguides

Abstract

Optical properties of multilayer InAs quantum dot waveguides, grown by molecular beam epitaxy, have been studied under applied electric field. Fabry-Perot measurements at 1515 nm on InAs/GaAs quantum dot structures yield a significantly enhanced linear electro-optic efficiency compared to bulk GaAs. Electro-absorption measurements at 1300 nm showed increased absorption with applied field accompanied with red shift of the spectra. Spectral shifts of up to 21% under 18 Volt bias was observed at 1320 nm. Krestnikov, A. R. Kovsh M. Fischer, and J. Koeth, "Enhanced In(Ga)As/GaAs quantum dot based electrooptic modulation at 1.55 µ m," Appl. Phys. Lett. 91, 91118 (2007).

InGaAs self-assembly quantum dot for high-speed 1300nm electroabsorption modulator

“…On comparing the work of Refs. [4,[8][9][10], our work shows clear QCSE and thus optical modulation with relatively short waveguide length (300 mm), suggesting that the strong exciton effect of QD covers inhomogenous broadening effect in dot size distribution. Therefore, further growth techniques to increase the dot density and uniformity of dot size, are still aspired to enhance the performance of extinction ratio.…”

“…On approaching higher dimensions of QCSE, the introduction of quantum dots (QDs) causes 3-dimensional (3D) carrier confinement. Therefore, such stronger exciton effect due to Coulombic interaction between electron and hole can have the potential to provide higher efficiecy EAM over other conventional types of active regions, such as QW and bulk material [1][2][3][4]. Based on the self-assembled InGaAs QD formation, the development of 3-dimensional quantum structure has been successfully and widely used in gain-related optoelectronic devices such as laser and optical amplifiers [5][6][7].…”

“…Based on the self-assembled InGaAs QD formation, the development of 3-dimensional quantum structure has been successfully and widely used in gain-related optoelectronic devices such as laser and optical amplifiers [5][6][7]. By such QD development, several groups have also worked on the QD application based on QCSE, such as electroabsorption properties, high-power excitation, high-speed carrier dynamics, and modulator performance [4,[8][9][10]. From the view, point of device application, EAM using well-developed quantum well (QW) material have been demonstrated with high-speed high-efficient performance by broadband microwave design and engineering [11,12].…”

Perspective: The future of quantum dot photonic integrated circuits

“…98 Measurements using InAs QDs for electro-optic modulation at 1515 nm showed a modulation efficiency of <1 V cm with an insertion loss of 3.1 dB/cm and for electro-absorption modulation at 1309 nm, an insertion loss of 30 dB/cm was obtained at 18 V reverse bias. 99 Optical modulation using QDs is an area that still needs more research to determine feasibility. One potential drawback is that the same decoupling between the gain and reservoir that is so beneficial to amplifiers and MLLs may limit the performance of QD modulators since depleting carriers will require scattering out of the large energy level spacings and prior depletion of the carrier density reservoir.…”

Quadratic Electro-Optic Effect and Electro Absorption Process of Multi-layer Spherical Quantum Dot Enhanced by Metal Nanoparticle

“…In the two past decades, the quadratic electro-optic (Kerr) effects (QEOE) and electro-absorption (EA) process in quantum dots have been used in switching and modulation devices for photonic integrated circuits [12][13][14]. Hence, considering their applications, there have been several studies on QEOE and EA of quantum dots [15][16][17][18].…”