Novel ultrafast structured EUV/x-ray sources from nonlinear optics

Coherent extreme-ultraviolet (EUV)/x-ray laser sources, structured in their temporal/spectral, spatial and angular momentum properties are emerging as unique tools to probe the nanoworld. One of key ingredients for emergence such sources is extraordinary coherence up-conversion infrared through highly nonlinear process high-order harmonic generation. In this contribution we will review advances during last decade that led generation EUV/xray circularly polarized attosecond pulses, vortices with time-varying orbital momentum, ultrafast vector vector/vortex beams, tunable combs or pulse trains time-dependent polarization states. The use being already applied investigation chiral matter magnetic materials. latter case, very promising achieve a complete understanding electronic spin interactions govern sub-femtosecond magnetization dynamics.