科罗拉多大学的Kyle Matsuda团队采用电场实现了反应分子的共振碰撞屏蔽。相关研究成果发表在2020年12月11日出版的《科学》。

完全控制分子相互作用，包括反应性损失，将开辟量子科学的新领域。

研究人员通过外加电场诱导共振偶极相互作用，证明了超冷化学反应速率的极端可调性。研究人员在第一激发旋转状态下制备了费米子铷钾分子，观察到当将电场强度调节为几个百分点时，化学反应速率的调制幅度达三个数量级。

在准二维几何中，研究人员精确地确定了碰撞的三个主要角动量投影的贡献。利用共振特性保护了分子不受损耗，并将反应速率抑制在背景值以下一个数量级，从而实现了极性分子在大电场中的长寿命。

附：英文原文

Title: Resonant collisional shielding of reactive molecules using electric fields

Author: Kyle Matsuda, Luigi De Marco, Jun-Ru Li, William G. Tobias, Giacomo Valtolina, Goulven Quéméner, Jun Ye

Issue&Volume: 2020/12/11

Abstract: Full control of molecular interactions, including reactive losses, would open new frontiers in quantum science. We demonstrate extreme tunability of ultracold chemical reaction rates by inducing resonant dipolar interactions by means of an external electric field. We prepared fermionic potassium-rubidium molecules in their first excited rotational state and observed a modulation of the chemical reaction rate by three orders of magnitude as we tuned the electric field strength by a few percent across resonance. In a quasi–two-dimensional geometry, we accurately determined the contributions from the three dominant angular momentum projections of the collisions. Using the resonant features, we shielded the molecules from loss and suppressed the reaction rate by an order of magnitude below the background value, thereby realizing a long-lived sample of polar molecules in large electric fields.

DOI: 10.1126/science.abe7370

Source: https://science.sciencemag.org/content/370/6522/1324