Design of organic semiconductor laser structures for low threshold operation

A theoretical analysis is undertaken of the optical mode confining properti es of novel DFB and DBR ridge guided lasers fabricated from organic semicon ducting materials. The analysis reveals that single transverse mode operati on of the laser is possible by virtue of the increased lateral confinement and favourable values for gain threshold are obtained. A design for an effi cient optical pumping arrangement is presented which makes use of the large Stokes-shift typical of organic semiconductors to employ a multi-periodic grating for both input and output coupling. Initial results of an analysis of this approach are also presented.