LULI, École Polytechnique, CNRS, CEA, UPMC, route de Saclay, 91128 Palaiseau, France.
Phys Rev Lett. 2012 Feb 3;108(5):055001. doi: 10.1103/PhysRevLett.108.055001. Epub 2012 Jan 30.
The dynamics of the focusing of laser-driven ion beams produced from concave solid targets was studied. Most of the ion beam energy is observed to converge at the center of the cylindrical targets with a spot diameter of 30 μm, which can be very beneficial for applications requiring high beam energy densities. Also, unbalanced laser irradiation does not compromise the focusability of the beam. However, significant filamentation occurs during the focusing, potentially limiting the localization of the energy deposition region by these beams at focus. These effects could impact the applicability of such high-energy density beams for applications, e.g., in proton-driven fast ignition.
研究了从凹面固体靶产生的激光驱动离子束聚焦的动力学。观察到大部分离子束能量集中在圆柱形靶的中心，光斑直径为 30μm，这对于需要高束能密度的应用非常有利。此外，不平衡的激光辐照不会影响束的聚焦能力。然而，在聚焦过程中会发生明显的细丝化，这可能会限制这些光束在焦点处的能量沉积区域的定位。这些效应可能会影响此类高能密度束在应用中的适用性，例如在质子驱动的快速点火中。
