The research topic of air lasing is of fundamental and practical importance, which has grown
rapidly in the past decade. Air lasing, or a laser‐like emission from air species including …

Scattering of classical light by atomic clouds induces photon-mediated effective long-range
interactions between the atoms and leads to cooperative effects even at low atomic …

We present an ameliorated arctangent algorithm based on phase-locked loop for digital
Doppler signal processing, utilized within the heterodyne detection system. We define the …

Tunable narrow-band short-pulse coherent emission can be generated by the optical
parametric amplification of a seeded continuous wave (CW) laser. However, the residual …

Resonant coherent Raman spectroscopy based on electronic transitions is known for over
40 years to provide chemically specific information from molecules at micromolar …

In this work, we report experimentally achieved optical gain of a weak probe beam in a three-
level Λ system in a low density Rubidium vapor cell driven by a single pump beam. The …

Tunable middle infrared generation is now affordable through optical parametric generation
and amplification in a number of infrared nonlinear crystals. However, maintaining narrow …

COVID-19 pandemic is calling for new methods of remote chemical sensing, which can
potentially detect small number of viral particles in air at safe distances. Raman …

Generation of tunable middle infrared radiation is important for a number of applications
ranging from biomedical imaging to remote sensing and imaging. Short laser pulses provide …

We investigate the collective spontaneous emission from an ensemble of two-level atoms
evenly distributed inside a sphere with a low density. An initial symmetric single-excitation …