• High Power Laser Science and Engineering
  • Vol. 8, Issue 4, 04000e41 (2020)
Dahui Wang1、2, Yinren Shou1, Pengjie Wang1, Jianbo Liu1, Zhusong Mei1, Zhengxuan Cao1, Jianmin Zhang2, Pengling Yang2, Guobin Feng2, Shiyou Chen1, Yanying Zhao1, Joerg Schreiber3, and Wenjun Ma1、*
Author Affiliations
  • 1State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing100871, China
  • 2State Key Laborartory of Laser Interaction with Matter, Northwest Institute of Nuclear Technology, Xi’an710024, China
  • 3Fakultät für Physik, Ludwig-Maximilians-University, D-85748Garching, Germany
  • show less

    Abstract

    Single-shot laser-induced damage threshold (LIDT) measurements of multi-type free-standing ultrathin foils were performed in a vacuum environment for 800 nm laser pulses with durations τ ranging from 50 fs to 200 ps. The results show that the laser damage threshold fluences (DTFs) of the ultrathin foils are significantly lower than those of corresponding bulk materials. Wide band gap dielectric targets such as SiN and formvar have larger DTFs than semiconductive and conductive targets by 1–3 orders of magnitude depending on the pulse duration. The damage mechanisms for different types of targets are studied. Based on the measurement, the constrain of the LIDTs on the laser contrast is discussed.

    1 Introduction

    The application of chirped-pulse amplification (CPA) in solid lasers has realized the output of lasers with femtosecond duration and petawatt-class power[1,2]. Interaction of such ultra-intense laser pulses with thin foils has generated protons up to 100 MeV and carbon ions close to 600 MeV (see Refs. [3–10]), which has potential applications in the fields of hadron therapy, fast-ignition laser fusion, isotope production, and proton radiography[11–14]. In particular, when the thicknesses of the foils are in the range of several nanometers to a few tens of nanometers, quasi-monoenergetic ions can be generated in the scheme of radiation pressure acceleration (RPA)[15–17]. When ultrathin targets are used, the damage caused by the prepulse energy should be avoided. For a high-power laser pulse with a contrast of 107–109 and intensity of ~1020 W/cm2, the prepulse intensity of amplified spontaneous emission (ASE) or prepulses is in the range of 1011–1013 W/cm2, which is high enough to damage many targets and significantly influence the acceleration process[18–20]. For the upcoming 10 PW class laser facilities such as ELI[21,22], the prepulse intensity will scale up with the increasing peak power. Hence, the choice of target material that can survive the prepulse energy would be a crucial issue for laser-driven ion acceleration.

    Copy Citation Text
    Dahui Wang, Yinren Shou, Pengjie Wang, Jianbo Liu, Zhusong Mei, Zhengxuan Cao, Jianmin Zhang, Pengling Yang, Guobin Feng, Shiyou Chen, Yanying Zhao, Joerg Schreiber, Wenjun Ma. Laser-induced damage thresholds of ultrathin targets and their constraint on laser contrast in laser-driven ion acceleration experiments[J]. High Power Laser Science and Engineering, 2020, 8(4): 04000e41
    Download Citation
    Category: Research Articles
    Received: Aug. 8, 2020
    Accepted: Oct. 26, 2020
    Published Online: Jan. 5, 2021
    The Author Email: Wenjun Ma (wenjun.ma@pku.edu.cn)