Defence R&D Canada, Valcartier Centre, Québec, G3J 1X5, Canada.
INRS-EMT, Varennes, J3X 1S2, Canada.
Sci Rep. 2017 Jan 5;7:40063. doi: 10.1038/srep40063.
Recent works on plasma channels produced during the propagation of ultrashort and intense laser pulses in air demonstrated the guiding of electric discharges along the laser path. However, the short plasma lifetime limits the length of the laser-guided discharge. In this paper, the conductivity and lifetime of long plasma channels produced by ultrashort laser pulses is enhanced efficiently over many orders of magnitude by the electric field of a hybrid AC-DC high-voltage source. The AC electric pulse from a Tesla coil allowed to stimulate and maintain the highly conductive channel during few milliseconds in order to guide a subsequent 500 times more energetic discharge from a 30-kV DC source. This DC discharge was laser-guided over an air gap length of two metres, which is more than two orders of magnitude longer than the expected natural discharge length. Long plasma channel induced by laser pulses and stimulated by an external high-voltage source opens the way for wireless and efficient transportation of energetic current pulses over long air gaps and potentially for guiding lightning.
最近关于在空气中传播的超短强激光脉冲产生的等离子体通道的研究工作表明，沿着激光路径引导放电。然而，短的等离子体寿命限制了激光引导放电的长度。在本文中，通过混合交流-直流高压源的电场，有效地将由超短激光脉冲产生的长等离子体通道的电导率和寿命增强了几个数量级。特斯拉线圈的交流电脉冲允许在几毫秒内激发和维持高导电性通道，以引导来自 30kV 直流源的后续能量高 500 倍的放电。该直流放电在两米的气隙长度上进行了激光引导，这比预期的自然放电长度长两个数量级以上。由激光脉冲诱导并由外部高压源激发的长等离子体通道为在长气隙中无线和高效地传输高能电流脉冲以及潜在地引导闪电开辟了道路。
