相关论文: Laser Noise Reduction in Air
We study the possibility of efficient self-compression of femtosecond laser pulses in nonlinear media with anomalous dispersion of group velocity during the self-focusing of wave packets with a power several times greater than the critical…
We study the suppression of noise degradation in high-power soliton-induced supercontinuum generation under the influence of plasma contributions in metallic dielectric-coated hollow waveguides. The high coherence of the supercontinuum is…
We have experimentally confirmed the presence of long-memory correlations in the wandering of a thin Gaussian laser beam over a screen after propagating through a turbulent medium. A laboratory-controlled experiment was conducted in which…
The femtosecond laser filamentation is the result of the dynamic interplay between plasma self-focusing and defocusing generated by the multiphoton/tunnel ionization of air molecules. This equilibrium allows the filament to stably propagate…
We probe the natural complex structures in the transparent insect wings by a simple, non-invasive, real time optical technique using both monochromatic and broadband femtosecond lasers. A stable, reproducible and novel diffraction pattern…
The generation of microwaves from optical signals suffers from thermal and shot noise inherent in the photodetection process. This problem is more acute at lower pulse repetition rates where photodiode saturation limits the achievable…
Fourier transform infrared (FTIR) spectrometers have been the dominant technology in the field of mid-infrared (MIR)spectroscopy for decades. Supercontinuum laser sources operating in the MIR spectral region now offer the potential to…
The theoretically predicted correlation of laser phase fluctuations in Lambda-type interaction schemes is experimentally demonstrated. We show, that the mechanism of correlation in a Lambda scheme is restricted to high frequency noise…
Rayleigh scattering generates intensity noise close to an optical carrier that propagates in a single-mode optical fiber. This noise degrades the performance of optoelectronic oscillators and RF-photonic links. When using a broad linewidth…
A theoretical study of power loss from periphery of an ultrashort pulse laser beam and temporally resolved defocussing produced by laser induced plasma are performed using paraxial approximation. Our analysis incorporate consideration of…
Density inhomogeneities along the line-of-sight distort fluctuations in the cosmic microwave background. Usually, this effect is thought of as a small second-order effect that mildly alters the statistics of the microwave background…
We characterize the phase noise of a microwave photonic channel, where a 10 GHz signal is carried by an intensity-modulated light beam over a short optical fiber, and detected. Two options are compared, (i) an electro-optic modulator (EOM),…
We present experimental and simulated results to quantify the impact of nonlinear noise in integrated photonic devices relying on spontaneous four-wave mixing. Our results highlight the need for design rule adaptations to mitigate the…
Light scattering in inhomogeneous media induces wavefront distortions which pose an inherent limitation in many optical applications. Examples range from microscopy and nanosurgery to astronomy. In recent years, ongoing efforts have made…
The detection and characterization of the physical properties of very distant galaxies will be one the prominent science case of all future Extremely Large Telescopes, including the 39m E-ELT. Multi-Object Spectroscopic instruments are…
Detection of quasi-monochromatic, long-duration (continuous) gravitational wave radiation emitted by, e.g., asymmetric rotating neutron stars in our Galaxy requires a long observation time to distinguish it from the detector's noise. If…
The propagation of intense picosecond laser pulses in air in the presence of strong nonlinear self-action effects and air ionization is investigated experimentally and numerically. The model used for numerical analysis is based on the…
We show that fast technical fluctuations of microwave signals can be strongly suppressed by cryogenic resonators. The experiments were carried out with sapphire resonators cooled to approximately 6 K at frequencies around 11 GHz. Each…
Modification of surface and volume of sapphire is shown to affect reflected and transmitted light at THz spectral range. Structural modifications were made using ultra-short 230 fs laser pulses at 1030 nm and 257.5 nm wavelengths forming…
Fast speckle suppression is crucial for time-resolved full-field imaging with laser illumination. Here, we introduce a method to accelerate the spatial decoherence of laser emission, achieving speckle suppression in the nanosecond…