Direct probe of spectral inhomogeneity reveals synthetic tunability of single-nanocrystal spectral linewidths

The spectral linewidth of an ensemble of fluorescent emitters is dictated by the combination of single-emitter linewidths and sample inhomogeneity. For semiconductor nanocrystals, efforts to tune ensemble linewidths for optical applications have focused primarily on eliminating sample inhomogeneitie...

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Bibliographic Details
Main Authors: Cui, Jian, Marshall, Lisa F., Chen, Ou, Brokmann, Xavier, Bawendi, Moungi G., Beyler, Andrew Paul, Harris, Daniel Kelly, Wanger, Darcy Deborah
Other Authors: Massachusetts Institute of Technology. Department of Chemistry
Format: Article
Language:en_US
Published: Nature Publishing Group 2014
Online Access:http://hdl.handle.net/1721.1/84988
https://orcid.org/0000-0003-2220-4365
https://orcid.org/0000-0002-5613-8928
Description
Summary:The spectral linewidth of an ensemble of fluorescent emitters is dictated by the combination of single-emitter linewidths and sample inhomogeneity. For semiconductor nanocrystals, efforts to tune ensemble linewidths for optical applications have focused primarily on eliminating sample inhomogeneities, because conventional single-molecule methods cannot reliably build accurate ensemble-level statistics for single-particle linewidths. Photon-correlation Fourier spectroscopy in solution (S-PCFS) offers a unique approach to investigating single-nanocrystal spectra with large sample statistics and high signal-to-noise ratios, without user selection bias and at fast timescales. With S-PCFS, we directly and quantitatively deconstruct the ensemble linewidth into contributions from the average single-particle linewidth and from sample inhomogeneity. We demonstrate that single-particle linewidths vary significantly from batch to batch and can be synthetically controlled. These findings delineate the synthetic challenges facing underdeveloped nanomaterials such as InP and InAs core–shell particles and introduce new avenues for the synthetic optimization of fluorescent nanoparticles.