Far-Infrared Absorption of PbSe Nanorods

• Published in: Nano letters Vol. 11; no. 7; pp. 2786 - 2790
• Main Authors: Hyun, Byung-Ryool, Bartnik, A. C, Koh, Weon-kyu, Agladze, N. I, Wrubel, J. P, Sievers, A. J, Murray, Christopher B, Wise, Frank W
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 13.07.2011
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Dielectrics; Electrostatics; Exact sciences and technology; Fullerenes and related materials; Infrared and raman spectra and scattering; Lead - chemistry; Materials science; Mathematical models; Nanocrystalline materials; Nanocrystals; Nanorods; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nanotechnology; Nanotubes; Nanotubes - chemistry; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Particle Size; Physics; Selenium Compounds - chemistry; Spectra; Spectrophotometry, Infrared; Splitting; Surface Properties; Visible and ultraviolet spectra; PbSe; far-infrared absorption; local field factor; nanorod; Fröhlich mode; Free carrier; Dielectric function; Lead selenides; Local field; Resonance; Infrared spectra; Absorption spectra; Aspect ratio; Electrostatics; Nanorod; Nanostructured materials; Nanocrystal
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl201115h

Measurements of the far-infrared absorption spectra of PbSe nanocrystals and nanorods are presented. As the aspect ratio of the nanorods increases, the Fröhlich sphere resonance splits into two peaks. We analyze this splitting with a classical electrostatic model, which is based on the dielectric function of bulk PbSe but without any free-carrier contribution. Good agreement between the measured and calculated spectra indicates that resonances in the local field factors underlie the measured spectra.