科羅拉多大學(xué)的Kyle Matsuda團(tuán)隊采用電場實現(xiàn)了反應(yīng)分子的共振碰撞屏蔽。相關(guān)研究成果發(fā)表在2020年12月11日出版的《科學(xué)》。

完全控制分子相互作用，包括反應(yīng)性損失，將開辟量子科學(xué)的新領(lǐng)域。

研究人員通過外加電場誘導(dǎo)共振偶極相互作用，證明了超冷化學(xué)反應(yīng)速率的極端可調(diào)性。研究人員在第一激發(fā)旋轉(zhuǎn)狀態(tài)下制備了費米子銣鉀分子，觀察到當(dāng)將電場強(qiáng)度調(diào)節(jié)為幾個百分點時，化學(xué)反應(yīng)速率的調(diào)制幅度達(dá)三個數(shù)量級。

(相關(guān)資料圖)

在準(zhǔn)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(xiàn)。利用共振特性保護(hù)了分子不受損耗，并將反應(yīng)速率抑制在背景值以下一個數(shù)量級，從而實現(xiàn)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

來源：科學(xué)網(wǎng) 小柯機(jī)器人

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