Interference observed in a double-slit experiment most conclusively demonstrates the wave properties of particles. We construct a quantum mechanical double-slit interferometer by rovibrationally exciting molecular deuterium (D₂) in a biaxial (v = 2, j = 2) state using Stark-induced adiabatic Raman passage, where v and j represent the vibrational and rotational quantum numbers, respectively. In D₂ (v = 2, j = 2) → D₂ (v = 2, j′ = 0) rotational relaxation via a cold collision with ground state helium, the two coherently coupled bond axis orientations in the biaxial state act as two slits that generate two indistinguishable quantum mechanical pathways connecting initial and final states of the colliding system. The interference disappears when we decouple the two orientations of the bond axis by separately constructing the uniaxial states of D₂, unequivocally establishing the double-slit action of the biaxial state. This double slit opens new possibilities in the coherent control of molecular collisions.

中文翻译：

---

用于分子散射的量子机械双缝

在双缝实验中观察到的干涉最确凿地证明了粒子的波动特性。我们使用斯塔克诱导的绝热拉曼通道，通过在双轴 ( v = 2, j = 2) 状态下振动激发分子氘 (D ₂ )构建量子力学双缝干涉仪，其中v和j代表振动和旋转量子数， 分别。在 D ₂ ( v = 2, j = 2) → D ₂ ( v = 2, j' = 0) 通过与基态氦的冷碰撞实现旋转弛豫，双轴状态下的两个相干耦合的键轴方向充当两个狭缝，产生连接碰撞系统初始状态和最终状态的两个无法区分的量子力学路径。当我们通过分别构建D ₂的单轴态来解耦键轴的两个方向时，干涉消失，明确地建立了双轴态的双缝作用。这种双缝为分子碰撞的相干控制开辟了新的可能性。