Femtosecond laser filamentation is a unique nonlinear optical phenomenon when high-
power ultrafast laser propagation in all transparent optical media. During filamentation in the …

Filamentation of ultra-short TW-class lasers recently opened new perspectives in
atmospheric research. Laser filaments are self-sustained light structures of 0.1–1 mm in …

Remote or standoff detection of greenhouse gases, air pollutants, and biological agents with
innovative ultrafast laser technology attracts growing interests in recent years. Hybrid …

Among currently available optical spectroscopic methods, Raman spectroscopy has
versatile application to investigation of dynamical processes of molecules leading to …

Ultrafast extreme ultraviolet (XUV) transient absorption is the process by which atoms and
molecules absorb light on a timescale faster than the lifetime of the states involved …

Air lasing from single ionized N 2+ molecules induced by laser filamentation in air has been
intensively investigated and the mechanisms responsible for lasing are currently highly …

In standard lasers, light amplification requires population inversion between an upper and a
lower state to break the reciprocity between absorption and stimulated emission. However …

We experimentally demonstrate the existence of long-lived coherent polarizations coupling
simultaneously ground state X (⁠ X 2 Σ g+⁠) to excited states A (⁠ A 2 Π u⁠) and B (⁠ B 2 Σ …

We show that the intensity of self-seeded N 2+ lasing at 391 nm, assigned to the B 2 Σ
u+(v′= 0)→ X 2 Σ g+(v′′= 0) emission, is enhanced by 2 orders of magnitude by …

Ultrafast ionization of atoms or molecules by intense laser pulses creates extremely non-
stationary ionic states. This process triggers attosecond correlated electron-hole dynamics …