Integrating light emitters based on III-V materials with silicon-based electronics is crucial for further increase in data transfer rates in communication systems since the indirect bandgap of silicon prevents its direct use as a light source. We investigate here InAs/InGaAlAs quantum dot (QD) structures grown directly on 5° off-cut Si substrate and emitting light at 1.5 μm, compatible with established telecom platform.
View Article and Find Full Text PDFControlling optical fields on the subwavelength scale is at the core of nanophotonics. Laser-driven nanophotonic particle accelerators promise a compact alternative to conventional radiofrequency-based accelerators. Efficient electron acceleration in nanophotonic devices critically depends on achieving nanometer control of the internal optical nearfield.
View Article and Find Full Text PDFWe present a comprehensive study of the temperature dependent electronic and optoelectronic properties of a tunnelling injection quantum dot laser. The optical power-voltage ( -) characteristics are shown to be correlated with the current-voltage (-) and capacitance-voltage (-) dependencies at low and elevated temperatures. Cryogenic temperature measurements reveal a clear signature of resonant tunnelling manifested in periodic responses of the - and - characteristics, which diminish above 60 K.
View Article and Find Full Text PDFCoherent control is a key experimental technique for quantum optics and quantum information processing. We demonstrate a new degree of freedom in coherent control of semiconductor quantum dot (QD) ensembles operating at room temperature using the tunneling injection (TI) processes in which charge carriers tunnel directly from a quantum well reservoir to QD confined states. The TI scheme was originally proposed and implemented to improve QD lasers and optical amplifiers, by providing a direct injection path of cold carriers thereby eliminating the hot carrier injection problem which enhances gain nonlinearity.
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