Single Nanowire Extinction Spectroscopy

Abstract

Here we show the first direct extinction spectra of single one-dimensional (1D) semiconductor nanostructures obtained at room temperature utilizing a spatial modulation approach. (1) For these materials, ensemble averaging in conventional extinction spectroscopy has limited our understanding of the interplay between carrier confinement and their electrostatic interactions. (2-4) By probing individual CdSe nanowires (NWs), we have identified and assigned size-dependent exciton transitions occurring across the visible. In turn, we have revealed the existence of room temperature 1D excitons in the narrowest NWs.

Spectroscopy and Microscopy of Graphene Oxide and Reduced Graphene Oxide

“…These measurements are part of a broader class of studies we have conducted to probe the photophysics of individual nanostructures [38][39][40][41][42]. Examples include CdSe nanowires [38][39][40][41][42], single-walled carbon nanotubes [42], and Au nanoparticles [42].…”

Thermodynamic analysis of defect formation in BiFeO3

“…Nanowires are modelled as infinite cylinders with infinite potential barrier at the boundary. For defining binding energies of Coulomb centres in these wires the approach developed in [14] is used. The Coulomb potential is averaged over lateral wave functions describing confined motion, and the one dimensional Coulomb problem is solved for obtained effective potential.…”

Imaging nano-objects by linear and nonlinear optical absorption microscopies

“…[14] This means that it is technically much easier to record spectra via SMS than PHI and TAM. To date SMS has been used to examine the plasmon resonances of metal nanoparticles and nanorods, [1-3, 12, 13, 30, 77, 92, 100, 114, 115] coupled metal particles, [54,99,103] and the exciton structure of semiconductor nanowires [51,107,108] and carbon nanotubes. [16,25,107,122] These measurements provide detailed information about the properties of these materials.…”