Accession Number:

ADA473573

Title:

Development of Highly Ordered Heterostructured Semiconductor Nanowire Arrays for Sub-Wavelength Optical Devices

Descriptive Note:

Final rept. Jul 2004-Mar 2007

Corporate Author:

TORONTO UNIV (ONTARIO) DEPT OF METALLURGY AND MATERIALS SCIENCE

Personal Author(s):

• Ruda, Harry
• Nair, Selvakumar

Report Date:

2007-06-01

Pagination or Media Count:

31.0

Abstract:

Methodology for efficient growth of semiconductor nanowires of several Il-VI ZnSe, ZnO, znS and III-VI GaAs, InSb nanowires was developed and optimized. Based on optical and transport characterization measurements, defect states responsible for quenching of band-edge luminescence were identified and post-growth treatments were devised to eliminate those defects and to achieve strong excitonic emission. Carrier trapping dynamics was elucidated by ultrafast time-resolved optical pump-probe measurements. Optimized ZnSe nanowires were shown to exhibit an exceptionally high photoconductive response of 22AW in a single nanowire transistor device. Manganese doped ZnO nanowires were fabricated and above room temperature ferromagnetism was achieved. Transport measurements showed these wires to be n-type with a degenerate carrier distribution. The experimental efforts were supplemented by modeling that included design of high Q-factor nanowire array photonic cavities using as well as a theory of excitons in nanowires.

Descriptors:

• *PHOTODETECTORS
• *PHOTOCONDUCTIVITY
• *FERROMAGNETISM
• *EXCITONS
• METHODOLOGY
• OPTIMIZATION
• PHOTONIC CRYSTALS
• NANOTECHNOLOGY
• CHEMICALS
• OPTICAL DETECTORS
• SEMICONDUCTORS
• CATALYSTS

Subject Categories:

• Optical Detection and Detectors

Distribution Statement:

APPROVED FOR PUBLIC RELEASE