Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Two-particle correlation effects seen in time-integrated FWM experiments. The strong signal observed at negative time delay, with a rise time exactly half the decay time, is in contradiction with theory for atomic systems and is a signature for Coulomb correlation between electrons and holes (1).
