arXiv subjects

Chunlei Xia

Publications and source records attributed to Chunlei Xia.

2 recordsLinked to original sources

arXiv2009

Photoabsorption by Volume Plasmons in Metal Nanoclusters

It is well known that plasmons in bulk metals cannot be excited by direct photoabsorption, that is, by coupling of volume plasmons to light. Here we demonstrate that the situation in nanoclusters of the same metals is entirely different. We have carried out a photodepletion measurement for Na_20 and Na_92 and identified a broad volume plasmon absorption peak centered slightly above 4 eV, revealing the possibility of optical excitation of volume-type collective electronic modes in a metallic system. The observed phenomenon is related to different selection rules for finite systems.

physics.atm-clus↗

arXiv2008

Evaporative attachment of slow electrons to alkali nanoclusters

The abundance spectrum of Na^-_{n~7-140} anions formed by low energy electron attachment to free nanoclusters is measured to be strongly and nontrivially restructured with respect to the neutral precursor beam. This restructuring is explained in quantitative detail by a general framework of evaporative attachment: an electron is captured by the long-range polarization potential, its energy is transferred into thermal vibrations, and dissipated by evaporative cooling. The data also affirm a formulated relation between the binding energies of cationic, neutral, and anionic clusters, and an adjustment to the prior values of dimer evaporation energies.

physics.atm-clus↗