Random surface texturing of an optically-thick film to increase the pathlength of scattered light rays, first proposed nearly thirty years ago, hasthus far remained the most effective approach for photon absorption over thewidest set of conditions. Here using recent advances in computationalelectrodynamics we describe a general strategy for the design of a silicon thinfilm applicable to photovoltaic cells based on a quasi-resonant approach tolight trapping where two partially-disordered photonic-crystal slabs, stackedvertically on top of each other, have large absorption that surpasses theLambertian limit over a broad bandwidth and angular range.
展开▼
