Description
Speaker:
Takashi Mukaiyama
Institute of Science Tokyo
Abstract:
Atoms in a coherent superposition of different momentum states enable high-precision measurements of physical quantities. Matter-wave interferometers typically exploit the entanglement between an atomic internal and motional states. The accumulated matter-wave phases along different paths are extracted from the interference signal of the internal states after the final pulse of the interferometer sequence. Achieving precise sensing requires exquisite control over both the internal and external states of individual quantum particles. Atoms and ions are ideal candidates for these applications, as their quantum states can be precisely manipulated using electronic and optical techniques.
Here we present our experimental demonstration of matter-wave interferometry of a trapped 171Yb+ ion in a three-dimensional motion, initiated by a momentum kick. We irradiate a mode-locked laser at 355 nm to bring the ion into a superposition of one spin state with no momentum and the other spin state with a momentum, namely a spin-motion entangled state. When the laser is applied along the direction diagonal to any of the trap principal axes, the moving half of the ion wave packet travels in a harmonic potential in a complicated way. After the free evolution time, we irradiate the second laser pulse to close the interferometer. Our experiment successfully observed matter-wave interference of ions in three-dimensional motion by exciting the motion of an ion. To realize a large interferometric area, we developed a technique to significantly expand the ion orbital area by rapidly moving the ion trap center. Additionally, we constructed the entire experimental setup on a rotatable optical table, allowing us to rotate the system for a future trial to detect rotation.