Abstract We discuss the concept of characteristic squeezing modes applied to a travelling-wave optical parametric amplifier pumped by an ultrashort pulse. The characteristic modes undergo decoupled single-mode squeezing transformations, and therefore they form a useful basis to describe the evolution of the entire multimode system. This provides an elegant and intuitive picture of quantum stati...

We experimentally demonstrate that a type-II pulsed optical parametric amplifier operated in a phaseinsensitive configuration works as a near-perfect classical optical amplifier whose noise figure approaches 3 dB at high gains. We further demonstrate that, when operated in a phase-sensitive configuration, this amplifier works as a quantum-optical amplifier whose noise figure goes below 3 dB and...

We present the first experimental demonstration of the ”optimal” and ”universal” quantum entangling process involving qubits encoded in the polarization (−→π ) of single photons. The structure of the ”quantum entangling machine” consists of the quantum injected optical parametric amplifier by which the contextual realization of the 1 → 2 universal quantum cloning and of the universal NOT (U-NOT...

A simple model of a two-mode non-resonant parametric amplifier is studied with special regard to non-classical features such as revivals and squeezing. The methods used apply for an arbitrary pump parameter. Detailed analytical and explicit expressions are given when the coupling of the two modes has an harmonic time-dependence. Despite its simplicity the model exhibits a very broad range of in...

Bright squeezed vacuum (BSV) can be obtained at the output of a high-gain traveling-wave optical parametric amplifier with the vacuum at the input. Without any special efforts, it is multimode both spatially and temporally. This means it comes as not Fourier-limited pulses and not diffractionlimited beams. At the same time, what theory describes well and what is required for most applications i...

The process of high-order harmonic generation leads to the production of a train of attosecond-duration extreme ultraviolet (XUV) pulses, with one pulse emitted per optical half-cycle. For attosecond pump-probe experiments, a single, isolated attosecond pulse is preferable, requiring an almost continuous spectrum. We show experimentally and numerically that the addition of a second laser field,...

We present an overview of the recent developments in nonlinear silicon photonics. There were significant advances in devices exploiting the ð2Þ and ð3Þ nonlinearities. Here, we discuss parametric amplification, wavelength conversion, supercontinuum generation, parametric oscillation, and frequency comb generation in siliconbased devices.

We build a parametric amplifier with Josephson field-effect transistor (JoFET) as the active element. The resonant frequency of device is tunable over range $2\phantom{\rule{0.2em}{0ex}}\mathrm{GHz}$. JoFET has $20\phantom{\rule{0.2em}{0ex}}\mathrm{dB}$ gain, $4\phantom{\rule{0.2em}{0ex}}\mathrm{MHz}$ instantaneous bandwidth, and 1-dB compression point $\ensuremath{-}125.5\phantom{\rule{0.2em}{...

We demonstrate the generation of 22.6 μJ of combined energy at 3 μm for sub-300fs pulses at a repetition rate of 1 kHz using a LGSe optical parametric amplifier (OPA). The LGSe OPA is pumped by the 140-fs 1.6 μm pulses from a 300-mW KTA optical parametric chirped pulse amplifier (OPCPA) based on an all-optical synchronization scheme. By using a highly-nonlinear fiber, the output of an erbium-do...