Gerard Mourou

Bio: Gerard Mourou is an academic researcher from École Polytechnique. The author has contributed to research in topics: Laser & Ultrashort pulse. The author has an hindex of 82, co-authored 653 publications receiving 34147 citations. Previous affiliations of Gerard Mourou include University of Michigan & San Diego State University.

Lasers for high focused intensity applications

Abstract: We present the theoretical limits for generation of high focused intensity laser. The important role of high- saturation-fluence materials is established and the use of regenerative chirped pulsed amplification to achieve high energy extraction from such materials is discussed. A regenerative chirped pulse amplification model and related experiments support the view that the surface damage threshold does not limit the range of useful laser materials to those with saturation fluence below the surface damage threshold. In addition the importance of phase measurement and control in providing well-defined conditions for experiments are noted.

Calculation of power density directly from diffraction integrals

Abstract: Direct intensity characterization from diffraction integrals is a promising technique for evaluating ultra-high field. The energy and momentum conservation for vector diffraction field are discussed to clarify the role of longitudinal field in the calculation.

Method for the production of ultrashort and ultrahigh peak power laser pulses and system for putting into practice this method

Abstract: The invention concerns a method for producing ultrashort and ultrahigh peak power laser pulses and a system for putting into practice this method. The production of ultrashort and ultrahigh peak power laser pulses is implemented by amplifying and compressing relatively long and low energy laser pulses to such ultra short and ultrahigh peak power pulses, and the use of the plasma compression technique for producing ultrashort and ultrahigh peak power pulses having a duration in the range of 20 femtoseconds (fs) or less and an energy of at least 10 Kilojoule (kJ), wherein a pump pulse (PP) in the order of picoseconds (ps) and a seed pulse (SS) are applied to the plasma cell (PLC), which are synchronized with one another and adapted to the plasma cell.

Synchronization of an Active-Passive Mode-Locked Nd:YAG Laser and a Mode-Locked Argon Ion Laser

Abstract: We report on the synchronization of pulses from an active-passive mode-1ocked Nd:YAG laser [1] to pulses from a mode-locked Ar ion laser. The jitter between the laser pulses was 18 ps (root mean square) with maximum deviations of ±30 ps over 18 shots. The addition of a synchronously pumped dye laser [2] to the YAG-Ar system would offer a picosecond tunable laser well synchronized to a high-power, high-energy laser. The low-energy dye pulses could also be amplified in dye cells pumped by the synchronous pulses from the mode-locked YAG laser. Applications include picosecond chemistry and laser fusion experiments.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Phd by thesis

Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

A roadmap for graphene

Abstract: Recent years have witnessed many breakthroughs in research on graphene (the first two-dimensional atomic crystal) as well as a significant advance in the mass production of this material. This one-atom-thick fabric of carbon uniquely combines extreme mechanical strength, exceptionally high electronic and thermal conductivities, impermeability to gases, as well as many other supreme properties, all of which make it highly attractive for numerous applications. Here we review recent progress in graphene research and in the development of production methods, and critically analyse the feasibility of various graphene applications.

Black Hole Explosions

Abstract: QUANTUM gravitational effects are usually ignored in calculations of the formation and evolution of black holes. The justification for this is that the radius of curvature of space-time outside the event horizon is very large compared to the Planck length (Għ/c3)1/2 ≈ 10−33 cm, the length scale on which quantum fluctuations of the metric are expected to be of order unity. This means that the energy density of particles created by the gravitational field is small compared to the space-time curvature. Even though quantum effects may be small locally, they may still, however, add up to produce a significant effect over the lifetime of the Universe ≈ 1017 s which is very long compared to the Planck time ≈ 10−43 s. The purpose of this letter is to show that this indeed may be the case: it seems that any black hole will create and emit particles such as neutrinos or photons at just the rate that one would expect if the black hole was a body with a temperature of (κ/2π) (ħ/2k) ≈ 10−6 (M/M)K where κ is the surface gravity of the black hole1. As a black hole emits this thermal radiation one would expect it to lose mass. This in turn would increase the surface gravity and so increase the rate of emission. The black hole would therefore have a finite life of the order of 1071 (M/M)−3 s. For a black hole of solar mass this is much longer than the age of the Universe. There might, however, be much smaller black holes which were formed by fluctuations in the early Universe2. Any such black hole of mass less than 1015 g would have evaporated by now. Near the end of its life the rate of emission would be very high and about 1030 erg would be released in the last 0.1 s. This is a fairly small explosion by astronomical standards but it is equivalent to about 1 million 1 Mton hydrogen bombs. It is often said that nothing can escape from a black hole. But in 1974, Stephen Hawking realized that, owing to quantum effects, black holes should emit particles with a thermal distribution of energies — as if the black hole had a temperature inversely proportional to its mass. In addition to putting black-hole thermodynamics on a firmer footing, this discovery led Hawking to postulate 'black hole explosions', as primordial black holes end their lives in an accelerating release of energy.

Materials for terahertz science and technology

Abstract: Terahertz spectroscopy systems use far-infrared radiation to extract molecular spectral information in an otherwise inaccessible portion of the electromagnetic spectrum. Materials research is an essential component of modern terahertz systems: novel, higher-power terahertz sources rely heavily on new materials such as quantum cascade structures. At the same time, terahertz spectroscopy and imaging provide a powerful tool for the characterization of a broad range of materials, including semiconductors and biomolecules.