Subwavelength optical elements (SOEs) and nanofabrications - a path to integrate optical communication components on a chip

Summary form only given. The paper presents a special class of optical devices, SOEs, which have feature size smaller than the wavelength of light and hence no non-zero order diffraction. SOEs drastically differ from bulk optics (i.e. ray optics) and diffractive optics in a number of ways. First, SOEs can perform conventional bulk optics functions, but with a size orders of magnitude smaller than bulk optics. Second, different SOEs can be made using the same materials but different nano-patterns, rather than different materials as in bulk optics. The two advantages make SOEs intrinsically suited for integration on a chip. Moreover, SOEs can offer new functionalities that bulk or diffractive optics do not have. SOE examples discussed include polarizers, beam splitters and combiners, waveplates, antireflection structures, filters (fixed or tunable), and lenses. Furthermore, integration of SOEs with lasers to control and tune laser properties (polarization, lasing mode and frequency, etc.) is explored. Finally, an innovative nanofabrication technology is described.