Effects of laser wavelength and density scalelength on absorption of   ultrashort intense lasers on solid-density targets
  Hot electron temperatures and electron energy spectra in the course of interaction between intense laser pulse and overdense plasmas are reexamined from a viewpoint of the difference in laser wavelength. The hot electron temperature measured by a particle-in-cell simulation is scaled by $I$ rather than $I \lambda^2$ at the interaction with overdense plasmas with fixed ions, where $I$ and $\lambda$ are the laser intensity and wavelength, respectively. 
Susumu Kato, Eiichi Takahashi, Tatsuya Aota, Yuji Matsumoto, Isao   Okuda, Yoshiro Owadano