I am interested about air ionization by the laser beam. Here I found a very good answer, but I would like to clarify it a bit more.
How about a continuous laser? For MPI (multiphoton ionization) based on answer linked above, we need $1\:\rm J$ of energy to ionize $1\:\rm m$ of air if $R=100\:\rm μm$. I note it as $E_1$. To ionize any length $L$ Energy will be $E=E_1 L$. To keep the air of length $L$ ionized continuously we need to send energy $E$ every $t$ seconds ($t$ is recombination time). Power will be $W=\frac Et=E_1 \frac Lt$. The question: what is recombination time? for SPI (single photon ionization) in the answer about it is mentioned as $10\:\rm ns$, but later for MPI it was mentioned as $100\:\rm ps$ which is confusing.
For $100$ meters of air to be continuously ionized with recombination time $10\:\rm ns$ we will get power $W=100/10^{−8}=10^{10}\:\rm Watt$, which is 10 gigawatts (maybe not feasible now).
My question: Is this approach to calculate laser power correct or did I miss something? What is typical recombination time for the normal air (normal pressure and temperature)?
And what about partial ionization? If I want to have air 10% ionized, then can I simply divide calculated power by 10 or not?
