标题： 空气中通过氮到氩的共振三次谐波光子交换实现的双向级联超荧光激光 显示英文标题

标题： Bidirectional cascaded superfluorescent lasing in air enabled by resonant third harmonic photon exchange from nitrogen to argon

摘要： 无腔激光在大气空气中的激发引起了对潜在物理机制的基本理解的强烈研究。 在本信中，我们确定了一种新的机制——第三谐波光子介导的共振能量转移路径，通过初始三光子激发被强261纳米脉冲照射的氮分子，导致氩气中的粒子数反转——该机制使得大气空气中实现双向双色级联激光。 通过进行泵浦-探测测量，我们明确表明这种级联激光来源于超荧光（SF），而不是受激自发辐射（ASE）。 这种能够产生双向多色相干脉冲的级联激光为远程传感应用开辟了新的可能性。 显示英文摘要

摘要： Cavity-free lasing in atmospheric air has stimulated intense research towards fundamental understanding of underlying physical mechanisms. In this Letter, we identify a new mechanism -- third harmonic photon mediated resonant energy transfer pathway leading to population inversion in argon via initial three-photon excitation of nitrogen molecules irradiated by intense 261 nm pulses -- that enables bidirectional two-color cascaded lasing in atmospheric air. By making pump-probe measurements, we conclusively show that such cascaded lasing results from superfluorescence (SF) rather than amplified spontaneous emission (ASE). Such cascaded lasing with the capability of producing bidirectional multicolor coherent pulses opens additional possibilities for remote sensing applications.