本文从经典力学和量子力学两个方面研究了自旋为S，质量为m，磁矩为mue的中性粒子在非均匀磁场中作二维运动的问题，该磁场为B_x = B '* x; B_y=-B'* y; B_z=B。经典地，我们发现当磁矩反平行于B时，只要K<sqrt{4/27}，粒子就被俘获。我们还发现，粘性摩擦，无论是平移或进动，不稳定的系统。用量子力学方法研究了自旋S=h_bar/2粒子在同一场中的量子力学问题。将K作为绝热哈密顿量微扰的一个小参数，我们发现粒子在被囚禁基态的寿命T_esc={T_vib}/{128 pi ^2} * exp{2/K}，其中T_vib是粒子在绝热势V=mue * 中的经典周期。|B（x，y）|
英文摘要：
We study, both classically and quantum-mechanically, the problem of a neutral particle with spin S, mass m and magnetic moment mue, moving in two-dimensions in an inhomogeneous magnetic field given by B_x=B'*x; B_y=-B'*y; B_z=B;
We identify K, the ratio between the precessional frequency of the particle and its vibration frequency, as the relevant parameter of the problem.
Classicaly, we find that when the magnetic moment is antiparallel to B, the particle is trapped provided that K<sqrt{4/27}. We also find that viscous friction, be it translational or precessional, destabilizes the system.
Quantum-mechanically, we study the problem of spin S=h_bar/2 particle in the same field. Treating K as a small parameter for the perturbation from the adiabatic Hamiltonian, we find that the lifetime T_esc of the particle in its trapped ground-state is T_esc={T_vib}/{128 pi^2} * exp{2/K} where T_vib is the classical period of the particle when placed in the adiabatic potential V=mue *|B(x,y)|
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A cryogenic neutral-atom platform with full optical access and 2-hour trap lifetime
Max-Planck-Institut für Quantenoptik（马克斯·普朗克量子光学研究所）；Fakultät für Physik, Ludwig-Maximilians-Universität München（慕尼黑大学物理学院）；Munich Center for Quantum Science and Technology（慕尼黑量子科学与技术中心）
