Laser wakefield accelerators (LWFAs) produce extremely high gradients enabling compact accelerators and radiation sources but face design limitations, such as dephasing, occurring when trapped electrons outrun the accelerating phase of the wakefield. Here we combine spherical aberration with a novel cylindrically symmetric echelon optic to spatiotemporally structure an ultrashort, high-intensity laser pulse that can overcome dephasing by propagating at any velocity over any distance. The ponderomotive force of the spatiotemporally shaped pulse can drive a wakefield with a phase velocity equal to the speed of light in vacuum, preventing trapped electrons from outrunning the wake. Simulations in the linear regime and scaling laws in the bubble regime illustrate that this dephasingless LWFA can accelerate electrons to high energies in much shorter distances than a traditional LWFA-a single 4.5 m stage can accelerate electrons to TeV energies without the need for guiding structures.

中文翻译：

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无相位激光尾场加速。

激光尾场加速器 (LWFA) 产生极高的梯度，可实现紧凑型加速器和辐射源，但面临设计限制，例如当被捕获的电子超过尾场的加速阶段时会发生相移。在这里，我们将球面像差与新型圆柱对称梯形光学器件相结合，在时空上构建超短、高强度激光脉冲，该脉冲可以通过以任何速度在任何距离上传播来克服相位差。时空成形脉冲的有质动力可以驱动相速度等于真空中光速的尾场，防止被捕获的电子超过尾流。