Abstract
Coherent superposition of light from subwavelength sources is an attractive prospect for the manipulation of the direction, shape and polarization of optical beams. This phenomenon constitutes the basis of phased arrays, commonly used at microwave and radio frequencies. Here we propose a new concept for phased-array sources at infrared frequencies based on metamaterial nanocavities coupled to a highly nonlinear semiconductor heterostructure. Optical pumping of the nanocavity induces a localized, phase-locked, nonlinear resonant polarization that acts as a source feed for a higher-order resonance of the nanocavity. Varying the nanocavity design enables the production of beams with arbitrary shape and polarization. As an example, we demonstrate two second harmonic phased-array sources that perform two optical functions at the second harmonic wavelength (∼5μm): a beam splitter and a polarizing beam splitter. Proper design of the nanocavity and nonlinear heterostructure will enable such phased arrays to span most of the infrared spectrum.
| Original language | English |
|---|---|
| Article number | 7667 |
| Journal | Nature Communications |
| Volume | 6 |
| DOIs | |
| State | Published - Jul 1 2015 |
| Externally published | Yes |
Funding
O.W. would like to acknowledge Mr Caner Guclu, University of California Irvine, for his assistance in the far field calculations, Dr Xuedan Ma, Sandia National Laboratories, for her assistance with SEM imaging and Dr Naama Wald for assistance in graphical designs of figures in this manuscript. This work was supported by the US Department of Energy (DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering and performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the US DOE Office of Science. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US DOE’s National Nuclear Security Administration under contract DE-AC04-94AL85000.