We report the attenuance and temperature-dependent photoluminescence spectra of PbSe nanowires with diameters between 5.6 and 26.4 nm (12−23% relative standard deviation) and lengths greater than 1 μm. The nanowire first exciton energy varies between 0.3 and 0.6 eV as the diameter decreases from 26.4 to 5.6 nm, respectively. Compared to spherical PbSe nanocrystals, PbSe nanowires show less quantum confinement and larger Stokes shifts. The band gap temperature coefficient (dE g/dT) decreases as the nanowire diameter decreases, consistent with previous results for PbSe spherical nanocrystals.

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We study the general problem of Raman resonances in arbitrary magnetic fields for realistic alkali atoms. We first present the details of a model that includes all magnetic sub-levels and their appropriate coupling strengths to two laser fields. The numerical implementation of this model and some of the results are also presented. Our experimental arrangement is described and preliminary measurements are presented.

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