Electrons are late starters
When physicists search for new semiconductors for chips or lasers, they have been able to rely on sophisticated computer programs - until now. However, it is possible that the models these programs have used to predict the electronic properties of a material oversimplify reality. An international team that includes researchers from the Max Planck Institute of Quantum Optics has now determined this from measurements with extremely short laser pulses. The physicists have concluded from this that electrons which a laser pulse knock out of an atom are catapulted from the particle with a delay of several tens of attoseconds. One attosecond corresponds to a billionth of a billionth of a second. The assumption so far has been that, during photoemission, electrons immediately shoot out when the light pulse impinges on the material. The models with which quantum physicists describe the electronic properties of matter are also based on the electrons...