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

作者:Cui Jian*; Beyler Andrew P; Marshall Lisa F; Chen Ou; Harris Daniel K; Wanger Darcy D; Brokmann Xavier; Bawendi Moungi G
来源:Nature Chemistry, 2013, 5(7): 602-606.
DOI:10.1038/NCHEM.1654

摘要

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.

  • 出版日期2013-7
  • 单位MIT

全文