Editor´s pick: Nonlinear scaling of strong field-driven multielectron emission
When electrons emitted from a sharp metal needle tip are driven strongly by the electric field of few-cycle laser pulses, they can rescatter at the tip surface. This effect is well-known from the generation of high harmonics, an achievement that was recognized with the Nobel Prize in 2023. When one measures the energy of these rescattered electrons, a prominent plateau appears. This plateau can be used to gauge optical near-field intensities precisely – so far, this method has only been applied in the single-electron regime for metal needle tips.
In our recent publication, we use this gauge to show that even in the multi-electron regime, well-known theoretical models from the single-particle regime remain valid for describing the electron dynamics. Furthermore, we demonstrate that even when the electron emission is heavily localized in space and time (only a few nanometers and hundreds of attoseconds), the emission statistics behave like a Poisson distribution, i.e., in an uncorrelated manner. In the future, such measurements could be used to investigate correlation effects, for example in superconductors.
Our article is published in the journal for Vacuum Science and Technology B, and was chosen as an Editor´s pick – thank you!