Continuous physical activity recognition for intelligent labour monitoring

Multimedia Tools and Applications - The paper addresses the problem of human activity recognition based on the data from wearable sensors. Human activity recognition depends on a wide context of...     

Comparative Analysis of Injection Microdisk Lasers Based on InGaAsN Quantum Wells and InAs/InGaAs Quantum Dots

Semiconductors - The results of comparative analysis of the spectral and threshold characteristics of room-temperature injection microdisk lasers of the spectral range 1.2×× μm with...     

Laser characteristics of an injection microdisk with quantum dots and its free-space outcoupling efficiency

The spectral, threshold, and power characteristics of a microdisk laser 31 μm in diameter with an active region based on InAs/InGaAs quantum dots, operating in the continuous-wave (cw) mode at room temperature are studied. The minimum threshold current density is 0.58 kA/cm², the subthreshold linewidth of the whispering-gallery mode is 50 pm at a wavelength lying in the range of 1.26–1.27 μm. The total power emitted into free space reaches ~0.1 mW in the cw mode, whereas the radiation power of the whispering-gallery modes is ~2.8%.     

Multilayer quantum-dot arrays of high bulk density

The possibility of the formation of multilayer (30 layers) InAs/GaAs quantum-dot arrays with high structural and optical quality is demonstrated at small spacer-layer thicknesses (30–15 nm). In the case of decreasing the spacer-layer thickness to 15 nm, significant radiation polarization is observed, which points to the electron coupling of individual quantum dots due to tunneling.