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The mechanism of using the anisotropic Purcell factor to control the spontaneous emission linewidths in a four-level atom is theoretically demonstrated; if the polarization angle bisector of the two dipole moments lies along the axis of large/small Purcell ...
The polarization-related properties of stimulated Brillouin scattering (SBS) processes in long, randomly birefringent, standard optical fibers are examined. Evolution equations for the pump and signal waves, in the presence of both birefringence and SBS, a ...
We demonstrate on-chip stimulated Brillouin scattering (SBS) in an As2S3 chalcogenide rib waveguide. SBS was characterized in a 7cm long waveguide with a cross-section 4μm x 850nm using the backscattered signal and pump-probe technique. The measured Brillo ...
We study absorption enhancement by light scattering at periodically textured interfaces in thin film silicon solar cells. We show that the periodicity establishes resonant coupling to propagating waveguide modes. Ideally, such modes propagate in the high i ...
A theoretical approach based on coupled-mode theory is presented in order to determine the radiation pattern of LEDs incorporating a shallow photonic crystal. From this, a fundamental limit for the directionality of the diffraction of a single guided mode ...
We report direct evidence of enhanced spontaneous emission in a photonic crystal light-emitting diode (LED) at telecom wavelength (lambda similar to 1300 nm). This result is crucial to obtain an electrically driven single photon source with high extraction ...
A detailed investigation and characterization of the local properties of individual nanoscopic structures is of great importance for the understanding of novel physical phenomena at the nanoscale as well as for the assessment of their possible use in futur ...
We measure the modal absorption coefficient of the InGaN quantum wells (QWs) in the absorber section of (Al,In)GaN multisection laser diodes as a function of bias voltage and photon energy using optical gain-spectroscopy. In the examined laser diodes, the ...
In this paper, a semi-classical formulation for modeling photonic-crystal (PC) structures with a four-layer multi quantum well (MQW) active region is presented. The formulation treats the electromagnetic fields as a classical entity, while employing the qu ...
We report direct evidence of enhanced spontaneous emission in a photonic-crystal (PhC) light-emitting diode. The device consists of p-i-n heterojunction embedded in a suspended membrane, comprising a layer of self-assembled quantum dots. Current is injecte ...