We investigate theoretically two-photon absorption spectroscopy modified by a control field in a confined Y-type four-level system. Dicke-narrowing effect occurs both in two-photon absorption lines and the dips of transparency against two-photon absorptio
Understanding the mechanisms of interaction between bone/bone marrow, circulatory system and nervous system is of great interest due to the potential clinical impact. In humans, the amount of knowledge in this domain remains relatively limited due to the
We demonstrate experimentally the application of a phase error detection method in the coherent beam combination (CBC) of a laser array. The method is based on the Hartmann micro-lens array. Both the piston and tilt errors can be detected and corrected si
A multipoint interferometer (MI), uniformly distributed point-like pinholes in a circle, was proposed to measure the orbital angular momentum (OAM) of vortex beams [Phys. Rev. Lett.101,