ABSTRACT
An analytical model for analyzing multi-channel intracavity spectroscopy technology (ICST) is established based on rate equations of Er-doped fiber laser. With the consideration of the amplified spontaneous emission, how the mode competition influences the iterative process for a stable output is analyzed. From the perspective of iterative times, the sensitivity-enhanced mechanism of the ICST is explained. Moreover, the theoretical modeling is employed to analyze the role that the mode-competition effect plays in switching the sensing channel automatically. It is demonstrated that, owing to the mode-competition effect in the laser cavity, the modulation of the cavity loss can be used to tune the sensing channel automatically. Furthermore, our proposed theoretical modeling is verified using a multi-channel ICST sensing system. It is indicated that the calculated estimates agree well with those data from the experimental absorption spectra. The principle will play a significant role in realizing the multiplexing of ICST.
ABSTRACT
PbSe quantum dot light emitting diodes (QD-LEDs) of a multi-layer architecture are reported in the present work to exhibit high external quantum efficiencies. In these devices, a ligand replacement technique was employed to activate PbSe QDs, and ZnO nanoparticles were used for the electron transport layer. The emission wavelength of this solution processed device is QD size tunable over a broad spectral range, and an LED efficiency of 0.73% was measured at 1412 nm. Higher efficiencies at longer wavelengths are also inferred from spectral characterization.
