A Plasma Perspective on Attosecond Science in Solids and in Gases
Ionization turns an atomic or molecular gas into a plasma with initial plasma parameters determined by atomic or molecular ionization physics. This obvious symbiosis encourages us to explore atomic ionization from a plasma perspective. When atoms are irradiated with intense light. That means that one should follow the sub-cycle motion of the newly formed electron (as one might for a plasma electron). The electron oscillates in the intense field, and it can collide with a near-by ion during this motion. In a plasma similar motion leads to inverse Bremsstrahlung, but in an atomic gas, high harmonics and attosecond pulses are produced provided the collision is between the electron and its parent ion. In this re-collision, infrared light is converted into much shorter wavelength light. Thus plasma physics leads us to a new form of extreme nonlinear optics.
I will describe attosecond pulse generation and measurement in solids and gases and why it is important.