On the Schwinger limit attainability with extreme power lasers

Plasma mirrors as a path to the Schwinger limit

Reaching light intensities above $10^{25}$ W/cm$^{2}$ and up to the Schwinger limit ($10^{29}$ W/cm$^{2}$) would enable testing decades-old fundamental predictions of Quantum Electrodynamics. A promising yet challenging approach to achieve such extreme fields consists in reflecting a high-power femtosecond laser pulse off a curved relativistic mirror. This enhances the intensity of the reflected beam by simultaneously compressing it in time down to the attosecond range, and focusing it to sub-micron focal spots. Here we show that such curved relativistic mirrors can be produced when an ultra-i…

载波包络相位和激光脉冲形状对超高斯非对称电场中Swinginger真空对偶产生的影响

Carrier envelope phase and laser pulse shape effects on Schwinger vacuum pair production in super-Gaussian asymmetric electric fields

研究了载波包络相位和激光脉冲形状对超高斯非对称电场中真空对产生影响，发现电场参数可使对数密度提升数倍。

Achieving extreme light intensities using relativistic plasma mirrors

In this letter, cutting-edge 3D Particle-In-Cell simulations are used to demonstrate that so-called relativistic plasma mirrors irradiated by PetaWatt (PW) lasers and naturally curved by laser radiation pressure can be used to tightly focus Doppler-generated harmonics to extreme intensities between $10^{25}-10^{26}W.cm^{-2}$. Those simulations are then employed to develop and validate a general 3D model of harmonic focusing by a curved relativistic plasma mirror. Finally, the insight gained from this model is used to propose novel all-optical techniques that would further increase the plasma m…

Coherent Harmonic Focusing and the Light Extreme

We demonstrate analytically and numerically that focusing of high harmonics produced by the reflection of a few femtosecond laser pulse from a concave plasma surface opens a new way towards unprecedentally high intensities. The key features allowing for boosting of the focal intensity is the harmonic coherency and the small exponent of the power-law decay of the harmonic spectrum. Using the similarity theory and direct particle-in-cell simulations we find that the intensity at the Coherent Harmonic Focus (CHF) scales as $I_{\tiny CHF} \propto a_0^3 I_0$, where $a_0$ and $I_0\propto a_0^2$ are …

Laser-driven plasma pinching in $e^{-}e^{+}$ cascade

The cascaded production and dynamics of electron-positron plasma in ultimately focused laser fields of extreme intensity are studied by 3D particle-in-cell simulations with the account for the relevant processes of quantum electrodynamics (QED). We show that, if the laser facility provides a total power above 20 PW, it is possible to trigger not only a QED cascade but also pinching in the produced electron-positron plasma. The plasma self-compression in this case leads to an abrupt rise of the peak density and magnetic (electric) field up to at least $10^{28}$ cm$^{-3}$ and 1/20 (1/40) of the …

Relativistic Tennis with Photons: Demonstration of Frequency Upshifting by a Relativistic Flying Mirror through Two Colliding Laser Pulses

Since the advent of chirped pulse amplification1 the peak power of lasers has grown dramatically and opened the new branch of high field science, delivering the focused irradiance, electric fields of which drive electrons into the relativistic regime. In a plasma wake wave generated by such a laser, modulations of the electron density naturally and robustly take the shape of paraboloidal dense shells, separated by evacuated regions, moving almost at the speed of light. When we inject another counter-propagating laser pulse, it is partially reflected from the shells, acting as relativistic flyi…