Filipp S, Klepp J, Hasegawa Y, Plonka-Spehr C, Schmidt U, Geltenbort P, Rauch H
Atominstitut der Osterreichischen Universitäten, Stadionallee 2, A-1020 Vienna, Austria.
Phys Rev Lett. 2009 Jan 23;102(3):030404. doi: 10.1103/PhysRevLett.102.030404. Epub 2009 Jan 22.
The geometric phase has been proposed as a candidate for noise resilient coherent manipulation of fragile quantum systems. Since it is determined only by the path of the quantum state, the presence of noise fluctuations affects the geometric phase in a different way than the dynamical phase. We have experimentally tested the robustness of Berry's geometric phase for spin-1/2 particles in a cyclically varying magnetic field. Using trapped polarized ultracold neutrons, it is demonstrated that the geometric phase contributions to dephasing due to adiabatic field fluctuations vanish for long evolution times.
几何相位已被提议作为脆弱量子系统抗噪声相干操纵的一个候选方案。由于它仅由量子态的路径决定，噪声涨落的存在对几何相位的影响方式与动力学相位不同。我们已经通过实验测试了在周期性变化磁场中自旋为1/2粒子的贝里几何相位的稳健性。利用捕获的极化超冷中子，证明了在长时间演化时，绝热场涨落对退相的几何相位贡献消失。
