Laser-driven positron production is expected to provide a non-radioactive, controllable, radiation tunable positron source in laboratories. We propose a novel approach of positron production by using a femto-second laser irradiating a microstructured surface target combined with a high-Z converter. By numerical simulations, it is shown that both the temperature and the maximum kinetic energy of electrons can be greatly enhanced by using a microstructured surface target instead of a planar target. When these energetic electrons shoot into a high Z converter, copious positrons are produced via Bethe-Heitler mechanism. With a laser (wavelength λ = 1 μm) with duration ~36 fs, intensity ~5.5 × 10²⁰ W/cm² and energy ~6 Joule, ~10⁹ positrons can be obtained.

预计激光驱动的正电子生产将在实验室中提供一种非放射性，可控制，可调谐辐射的正电子源。我们提出了一种新的正电子生产方法，通过使用飞秒激光辐照结合高Z转换器的微结构化表面靶材来进行。通过数值模拟表明，通过使用微结构化的表面靶代替平面靶，可以大大提高电子的温度和最大动能。当这些高能电子射入高Z转换器时，通过Bethe-Heitler机制产生大量正电子。使用持续时间约36 fs，强度约5.5×10 ²⁰ W / cm ²和能量约6焦耳的激光（波长λ= 1μm），可获得约10 ^9个正电子。