Related papers: Collection of remote optical signals by air wavegu…
The distant projection of high peak and average power laser beams in the atmosphere is a longstanding goal with a wide range of applications. Our early proof-of-principle experiments [Phys. Rev. X 4, 011027 (2014)] presented one solution to…
High-gain optical parametric amplification is an important nonlinear process used both as a source of coherent infrared light and as a source of nonclassical light. In this work, we experimentally demonstrate an approach to optical…
We demonstrate that femtosecond filaments can set up an extended and robust thermal waveguide structure in air with a lifetime of several milliseconds, making possible the very long range guiding and distant projection of high energy laser…
The increasing availability of high-power Yb-based ultrafast laser-amplifier systems has opened the possibility of air filamentation at high repetition rates >1 kHz. In this new regime, accumulation effects cannot be ruled out, therefore,…
Fundamental to many applications of laser pulses in science and technology is an extended interaction length with matter that significantly exceeds the distance over which the pulse would normally diffract and transversely spread. At low…
We discover long-lived (microsecond-scale) optical waveguiding in the wake of atmospheric laser filaments. We also observe the formation and then outward propagation of the consequent sound wave. These effects may be used for remote…
We present direct measurements of the gas acoustic dynamics following interaction of spatial single- and multi-mode 50 fs, 800 nm pulses in air at 10 Hz and 1 kHz repetition rates. Results are in excellent agreement with hydrodynamic…
Detection of radioactive material at distances greater than the radiated particle range is an important goal with applications in areas such as national defense and disaster response. Here we demonstrate avalanche-breakdown-based remote…
We investigate the feasibility of detecting extensive air showers by the radar technique at viewing angles smaller than $\sim 25^\circ$ to the shower axis. Considering a bistatic radar setup and shower geometries in which the receiver…
Reflection of radio waves off the short-lived plasma produced by the high-energy shower particles in the air is simulated, considering various radar setups and shower geometries. We show that the plasma produced by air showers has to be…
The use of optical fiber as sensor as well as transmission medium for sensing data is discussed, enabling the use of optically active sensors without power supply at distances of tens of kilometers. Depending on the interrogation system, a…
We present a novel remote gas detection and identification technique based on correlation spectroscopy with a piezoelectric tunable fibre-optic Fabry-P\'erot filter. We show that the spectral correlation amplitude between the filter…
The need for molecular standoff detection has motivated the development of a remotely pumped, high gain air laser that produces lasing in the backward direction and can sample the air as the beam returns. High gain is achieved in the near…
Femtosecond laser filament-induced plasma spectroscopy (FIPS) demonstrates great potentials in the remote sensing for identifying atmospheric pollutant molecules. Due to the widespread aerosols in atmosphere, the remote detection based on…
Slow waves and tunneling waves can meet at the cutoff wavelengths and/or transmission band edges of optical and quantum mechanical waveguides. The experimental investigation of this phenomenon, previously performed using various optical…
An improved method of remote optical absorption spectroscopy and hyperspectral optical absorption imaging is described which takes advantage of the photoacoustic remote sensing detection architecture. A wide range of photoacoustic…
Beam tracking is an essential functionality of millimeter wave (mmWave, 30-100 GHz) and sub-terahertz (sub-THz, 100-300 GHz) 5G/6G systems. It operates by performing antenna sweeping at both base station (BS) and user equipment (UE) sides…
Phase-sensitive amplification of squeezed states is a technique to mitigate high detection loss, e.g. at 2-micrometre wavelengths. Our analytical model of amplified squeezed states expands on the effect of phase noise and derives two…
We propose a new post-processing technique for the detection of faint companions from a sequence of adaptive optics corrected short exposures. The algorithm exploits the difference in shape between the on-axis and off-axis irradiance…
In order to enhance LIDAR performance metrics such as target detection sensitivity, noise resilience and ranging accuracy, we exploit the strong temporal correlation within the photon pairs generated in continuous-wave pumped semiconductor…