2025-07-28 マサチューセッツ工科大学(MIT)
MITの研究チームは、二重スリット実験を単一原子と単一光子によって理想化し、量子の本質に迫る実験を実施した。超低温下で配列された原子格子をスリットとし、各原子に1つの光子を散乱させることで、波動性と粒子性の関係を精密に検証。測定で粒子の情報を得るほど干渉パターンは消失し、ボーアの補完性原理を支持した。成果は『Physical Review Letters』に掲載され、量子力学の基本原理を実証する内容となっている。
Schematic of the MIT experiment: Two single atoms floating in a vacuum chamber are illuminated by a laser beam and act as the two slits. The interference of the scattered light is recorded with a highly sensitive camera depicted as a screen. Incoherent light appears as background and implies that the photon has acted as a particle passing only through one slit. Credit: Courtesy of the researchers
＜関連情報＞
- https://news.mit.edu/2025/famous-double-slit-experiment-holds-when-stripped-to-quantum-essentials-0728
- https://journals.aps.org/prl/abstract/10.1103/zwhd-1k2t
単一原子波束による一致光散乱と不一致光散乱 Coherent and Incoherent Light Scattering by Single-Atom Wave Packets
Vitaly Fedoseev, Hanzhen Lin (林翰桢), Yu-Kun Lu, Yoo Kyung Lee, Jiahao Lyu, and Wolfgang Ketterle
Physical Review Letters Published: 22 July, 2025
DOI: https://doi.org/10.1103/zwhd-1k2t
Abstract
We study light scattering of atomic wave packets in free space and discuss the results in terms of atom-photon entanglement and which-way information. Using ultracold atoms released from an optical lattice, we realize a Gedanken experiment which interferes single photons scattering off of Heisenberg uncertainty-limited wave packets. We unify the free-space and trapped-atom pictures by measuring the light scattered before and during wave packet expansion and show the coherence properties of the scattered light are independent of the presence of the trap. Therefore, recoilless scattering in a trap (Mössbauer effect), the different frequency of sidebands, and the excitation of an excited harmonic oscillator state are not essential to the question of which fraction of light scattering is coherent or incoherent. Our experiment demonstrates the potential of using atomic Mott insulators to create single-atom wave packets for fundamental studies.
