Semiconductor cascade lasers have larger photon noise than conventional semiconductor lasers as a result of positive correlations in photon emission in different gain stages which are connected electrically in series. The photon noise of a cascade laser can be related to the photon noise of a single-stage laser with a scaled external circuit impedance. This scaling relation for the photon noise...

Background: Au nanoparticles (AuNPs) exhibit very unique physiochemical and optical properties, which now are extensively studied in a range of medical diagnostic and therapeutic applications. AuNPs can be used for cancer clinical treatment with minimal invasion. On the other hand, curcumin is a polyphenol derived from turmeric which is used for medical purposes due to its anti...

Reduction of the intensity noise in semiconductor lasers is an important subject for the higher performance of an application. Simultaneous usage of the superposition of high frequency current and the electric negative feedback loop was proposed to suppress the noise for the higher power operation of semiconductor lasers. Effective noise reduction of more than 25 dB with 80 mW operation was exp...

Semiconductor lasers are the most widely used type of lasers. The very broad area of applications makes them almost indispensable in our every day life. We find them in CD and DVD players, in laser printers or in supermarkets. Semiconductor lasers can be very easy integrated in the optical systems and they have found numerous applications in science, technology, industry and medicine. We should...

The output spectrum of both gas and semiconductor lasers usually contains more than one frequency. Multimode operation in gas versus semiconductor lasers arises from different physics. In gas lasers, slow equilibration of the electron populations at different energies makes each frequency an independent single-mode laser. The slow electron diffusion in semiconductor lasers, combined with the sp...