Effective Transfer Efficiency Research Articles

Yb3+ to Er3+ energy transfer in LiNbO3

The energy transfer between and ions in lithium niobate is investigated and modelled using the rate equation formalism. An efficient energy transfer from to is found and the transfer and back-transfer coefficients have been determined ( and , respectively). Using the rate equation formalism it is shown that population inversion of the level (upper laser level at ) is attainable at sufficiently low pumping levels, making this material suitable for laser applications. The effective transfer efficiency is also calculated, showing good agreement with the experimental values obtained from the increase of the emission.

Device design with automatic simulation system for basic CCD characteristics

A simulation system has been developed to automatically analyze basic electrical characteristics of a charge-coupled device (CCD) image sensor from a process simulation result. This system shortened the simulation period to approximately 1/10 by getting rid of complicated repetitious procedures. A high-performance new cell technology has been developed successfully with improving impurity distribution in shorter development time by using this system. This technology has been realized as a CCD cell pixel with CCD charge quantity of 1.8 times, effective transfer efficiency of over 99%, no image lag for driving read-out pulse voltage in comparison with conventional technology. A 1/4-in 330 K square pixel progressive-scan CCD was fabricated with this technology. These results are described to demonstrate the effectiveness of the automatic simulation system.