電場作用下反應分子的共振碰撞屏蔽
作者:
小柯機器人發布時間:2020/12/14 16:07:46
科羅拉多大學的Kyle Matsuda團隊採用電場實現了反應分子的共振碰撞屏蔽。相關研究成果發表在2020年12月11日出版的《科學》。
完全控制分子相互作用,包括反應性損失,將開闢量子科學的新領域。
研究人員通過外加電場誘導共振偶極相互作用,證明了超冷化學反應速率的極端可調性。研究人員在第一激發旋轉狀態下製備了費米子銣鉀分子,觀察到當將電場強度調節為幾個百分點時,化學反應速率的調製幅度達三個數量級。
在準二維幾何中,研究人員精確地確定了碰撞的三個主要角動量投影的貢獻。利用共振特性保護了分子不受損耗,並將反應速率抑制在背景值以下一個數量級,從而實現了極性分子在大電場中的長壽命。
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