High density carbon (HDC) ablator is one of the promising candidates toward thermonuclear ignition in inertial confinement fusion (ICF), but it shows the largest ablation front instability growth as compared to other traditional ablator materials. In this Letter, we propose a novel HDC-CH capsule design, opening the way to mitigate the hydrodynamic instabilities by using CH as the outermost ablator layer, while keeping HDC as the main ablator for maintaining the advantage of short laser pulses. The CH layer is completely ablated during the shock transit phase. In the HDC-CH design, it is the first shock reflected from the HDC/CH interface that meets the ablation front first, which reduces the ablation front growth factor by about one order of magnitude at peak implosion velocity due to the Richtmyer-Meshkov and the Rayleigh-Taylor instabilities. Our 2D simulation studies demonstrate convincingly that the ablation front growth factor of the HDC-CH capsule can be significantly reduced at both the end of shock transit phase and the time at peak implosion velocity, as compared to a HDC capsule. This novel HDC-CH capsule not only keeps the main advantage of the HDC ablator, but also has the advantage of low hydrodynamic instabilities, which can provide a larger margin toward ICF ignition. It can be applicable to both indirect-drive and direct-drive targets.

中文翻译：

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减轻惯性约束聚变中水动力不稳定性增长的新型靶设计

高密度碳（HDC）烧蚀剂是惯性约束聚变（ICF）中热核点火的有希望的候选者之一，但与其他传统烧蚀剂材料相比，它显示出最大的烧蚀锋面不稳定性增长。在这封信中，我们提出了一种新颖的HDC-CH胶囊设计，通过使用CH作为最外层的烧蚀层，为保持流体动力学不稳定性开辟了道路，同时保持HDC为主要烧蚀层，以保持短激光脉冲的优势。在冲击过渡阶段，CH层被完全烧蚀。在HDC-CH设计中，是HDC / CH界面反射的第一个冲击首先与消融锋面相遇，这由于Richtmyer-Meshkov和瑞利泰勒不稳定性。我们的2D模拟研究令人信服地表明，与HDC胶囊相比，HDC-CH胶囊的消融前端生长因子在冲击传递阶段结束时和峰值内爆速度下的时间都可以显着降低。这种新颖的HDC-CH胶囊不仅保留了HDC消融器的主要优点，而且还具有较低的流体动力学不稳定性，可为ICF点火提供更大的余量。它可以同时适用于间接驱动目标和直接驱动目标。而且还具有水动力不稳定性低的优势，可以为ICF点火提供更大的余量。它可以同时适用于间接驱动目标和直接驱动目标。而且还具有水动力不稳定性低的优势，可以为ICF点火提供更大的余量。它可以同时适用于间接驱动目标和直接驱动目标。