Three‐Dimensional Particle‐In‐Cell Simulations of Electron‐Only Magnetic Reconnection Between Laser‐Produced Plasma Bubbles

Electron‐only magnetic reconnection, a novel type of reconnection where only electron dynamics is involved, has recently been observed in turbulent plasmas in the Earth's magnetosphere. In this letter, using particle‐in‐cell simulations, we demonstrate that electron‐only reconnection can be created via laser‐plasma interactions. The reconnection current sheet is carried by electrons, and its width is at the electron inertial scale. Moreover, only electron outflow is observed, while the ion outflow is negligible. The duration of the reconnection is found to be within the electron scale, thus there is no sufficient time for ions to respond. The energy conversion during electron‐only reconnection mainly occurs in the vicinity of the X‐line, and is dominated along the perpendicular direction. By analyzing the Poynting flux patterns, we find that the reconnection electric field dominates the whole energy conversion. This study advances our knowledge of the energy dissipation mechanism in the electron‐only reconnection regime. Plain Language Summary Magnetic reconnection is a fundamental energy converting process that occurs in space and laboratory plasma. Generally, magnetic reconnection involves both ion dynamics and electron dynamics. Recently, a new type of magnetic reconnection has been discovered in the Earth's turbulent magnetosheath and magnetotail, which is called electron‐only reconnection. In electron‐only reconnection, only electron outflow is observed since there is no time and/or space for ions to couple. In this study, by performing numerical simulations, we create the electron‐only reconnection via laser‐plasma interaction, and investigate the energy conversion during reconnection in detail. We find that both the spatial and temporal scale of the reconnection is within the electron scale. During magnetic reconnection, energy is transferred from the electromagnetic fields to the electrons, mainly occurring near the X‐line. The reconnection electric field plays a crucial role in energy conversion. This study improves our understanding of how energy is converted to electrons in electron‐only reconnection. Key Points Simulations show that electron‐only magnetic reconnection can be created via laser‐plasma interactions Both the spatial and temporal scales of the reconnection are at the electron scale, and only electron outflow is observed Energy conversion mainly occurs in the vicinity of the X‐line, and is driven by the reconnection electric field