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 …

Air lasing is a concept that refers to remote no-cavity (mirrorless) optical amplification in
ambient air with the air constituents as the gain media. Due to the high potential of air lasing …

A fine manipulation of population transfer among molecular quantum levels is a key
technology for control of molecular processes. When a light field intensity is increased to the …

We experimentally investigated the rotationally resolved polarization characteristics of N 2+
lasing at 391 and 428 nm using a pump-seed scheme. By varying the relative angle …

We experimentally investigate air lasing emission from singly ionized nitrogen molecules
exposed to bicircular two-color (BTC) femtosecond laser pulses. The light driven electron …

Molecular ions, produced via ultrafast ionization, can be quantum emitters with the aid of
resonant electronic couplings, which makes them the ideal candidates to study strong-field …

We simulate the pump-probe experiments of lasing in molecular nitrogen ions with particular
interest in the effects of rotational wave-packet dynamics. Our computations demonstrate …

Recently, the significant enhancement of N 2+ lasing realized with the help of a polarization-
gated intense 800-nm pump provides crucial clues to optimize both ionization and …

We investigate postionization population transfer processes among the three low-lying
electronic states—X 2 Σ g+, A 2 Π u, and B 2 Σ u+—of N 2+ created in an ultrashort-pulsed …

Air lasing in the nitrogen molecular ion is not well understood because the complex physics
responsible for gain is interwoven with pulse propagation in an extreme environment. Here …