Coherent control of ultrafast molecule making from colliding reactants is crucial for realizing coherent control of binary photoreactions (CCBP). To handle diverse excitation scenarios, feasibility with both weak and strong fields is essential. We experimentally demonstrate here the weak-field feasibility, achieving it even under thermally hot conditions typical of chemical reactions. The making of KAr complexes from hot pairs of colliding K and Ar atoms via resonance-mediated two-photon excitation is controlled by weak linearly chirped femtosecond pulses. Negative chirps enhance the yield. Our experimental and ab initio theoretical results are in excellent agreement. New routes to CCBP are opened.

中文翻译：

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超快分子制造的弱场相干控制


对碰撞反应物产生的超快分子的相干控制对于实现二元光反应 （CCBP） 的相干控制至关重要。为了处理不同的激励场景，弱场和强场的可行性都是必不可少的。我们在这里通过实验证明了弱场可行性，即使在化学反应的典型热条件下也能实现。通过共振介导的双光子激发，由碰撞的 K 和 Ar 原子的热对组成 KAr 复合物，由微弱的线性啁啾飞秒脉冲控制。负啁啾声可提高产量。我们的实验和从 头理论结果非常一致。开通了通往 CCBP 的新路线。