Optical Attoclock using Terahertz Radiation

Dynamics of optical tunneling is one of the central topics of attosecond science. The most prominent method to access attosecond-long delays in course of electron ionization is known as attoclock [1,2]. In the attoclock procedure, electrons ionized by a nearly-circularly polarized optical field are detected by a remote detector. The electric field of the driver pulse plays a role of a clock hand rotating with the optical frequency. Ionization delays lead to an angular shift of the electronic distribution at the detector. However, to access ionization dynamics one needs to "unwind" the electron path from the detector back to the core [3], making the physical insight rather cumbersome.