Movable high-Q nanoresonators realized by semiconductor nanowires on a Si photonic crystal platform

• Published in: Nature materials 2014-03, Vol.13 (3), p.279-285
• Main Authors: Birowosuto, Muhammad Danang, Yokoo, Atsushi, Zhang, Guoqiang, Tateno, Kouta, Kuramochi, Eiichi, Taniyama, Hideaki, Takiguchi, Masato, Notomi, Masaya
• Format: Article
• Language: English
• Subjects: 639/301/1019/1021; 639/301/1019/1022; 639/301/357/1016; 639/301/357/551; Biomaterials; Circuits; Condensed Matter Physics; Confinement; Corrugated waveguides; Crystallography; Devices; Electrical engineering; Emissions; Materials Science; Nanostructure; Nanotechnology; Nanowires; Optical and Electronic Materials; Optical properties; Photonics; Semiconductors; Silicon
• ISSN: 1476-1122; 1476-4660
• DOI: 10.1038/nmat3873

Subwavelength semiconductor nanowires have recently attracted interest for photonic applications because they possess various unique optical properties and offer great potential for miniaturizing devices. However, realizing tight light confinement or efficient coupling with photonic circuits is not straightforward and remains a challenge. Here we show that a high- Q nanocavity can be created by placing a single III–V semiconductor nanowire with a diameter of under 100 nm in a grooved waveguide in a Si photonic crystal, by means of nanoprobe manipulation. We observe very fast spontaneous emission (91 ps) from nanowires accelerated by the strong Purcell enhancement in nanocavities, which proves that very strong light confinement can be achieved. Furthermore, this system enables us to move the nanocavity anywhere along the waveguide. This configuration provides a significant degree of flexibility in integrated photonics and permits the addition and displacement of various functionalities of III–V nanocavity devices in Si photonic circuits. Confining light in subwavelength nanowires has posed a challenge to harnessing their potential for integrated photonic devices. Now, it is shown that a high- Q cavity can be achieved by placing a single nanowire into a groove in a photonic crystal resonator.