We use quantum electrodynamics particle-in-cell simulation to study the generation of dense electron–positron plasma and strong γ-ray bursts in counter-propagating laser beam interactions with two different solid targets, i.e. planar (type I) and convex (type II). We find that type II limits fast electron flow most effectively. while the photon density is increased by about an order of magnitude and energy by approx. 10%–20% compared with those in type I target. γ-photon source with an ultrahigh peak brilliance of 2נ10²⁵ photons/s/mm²/mrad²/0.1% BW is generated by nonlinear Compton scattering process. Furthermore, use of type II target increases the positron density and energy by 3 times and 32% respectively, compared with those in type I target. In addition, the conversion efficiencies of total laser energy to γ-rays and positrons of type II are improved by 13.2% and 9.86% compared with type I. Such improvements in conversion efficiency and positron density are envisaged to have practical applications in experimental field.

我们使用量子电动力学粒子内模拟研究了在与两个不同固体目标（即平面（I型）和凸形（II型））反向传播的激光束相互作用中密集的电子-正电子等离子体和强γ射线爆发的产生）。我们发现II型最有效地限制了快速电子流动。而光子密度大约增加一个数量级，能量大约增加一个数量级。相较于第一类目标者，为10％–20％。γ光子源，具有2high10 ²⁵光子/ s / mm ² / mrad ²的超高峰值亮度/0.1% BW是通过非线性康普顿散射过程产生的。此外，与I型靶相比，使用II型靶可使正电子密度和能量分别增加3倍和32％。另外，总激光能量向II型γ射线和正电子的转换效率比I型提高了13.2％和9.86％。这种转换效率和正电子密度的提高被认为在实验领域具有实际应用。