Size-dependent chemical transformation, structural phase change, and optical properties of nanowires

Abstract

Nanowires offer a unique approach for the bottom-up assembly of electronic and photonic devices with the potential of integrating photonics with existing technologies. The anisotropic geometry and mesoscopic length scales of nanowires also make them very interesting systems to study a variety of size-dependent phenomenon where finite-size effects become important. We will discuss the intriguing size-dependent properties of nanowire systems with diameters in the 5–300 nm range, where finite-size and interfacial phenomena become more important than quantum mechanical effects. The ability to synthesize and manipulate nanostructures by chemical methods allows tremendous versatility in creating new systems with well-controlled geometries, dimensions, and functionality, which can then be used for understanding novel processes in finite-sized systems and devices.

Keywords:

• nanowires
• phase transitions
• nanophotonics

Acknowledgements

This work was supported by the NSF-CAREER award (ECS-0644737), NSF (DMR-0706381 and DMR-1002164), and Penn-MRSEC (DMR05-20020 and DMR11-20901); Materials Structures and Devices Center at MIT, NSF-US Army Research Office under Grant No. W911NF-09-1-0477 and W911NF-11-1-0024; and the National Institutes of Health through the NIH Director’s New Innovator Award Program, 1-DP2-7251-01.