论文标题
Landau-Zener转变具有激发状态的能量依赖性衰减速率
Landau-Zener transition with energy-dependent decay rate of the excited state
论文作者
论文摘要
Landau-Zener转变的一个显着特征是激发态衰减率的生存概率不敏感。也就是说，最初处于基态的粒子的概率保持在同一状态对衰减不敏感，这是由于例如耦合到连续[V. M. Akulin和W. P. Schleich，物理。 Rev. A 46，4110（1992）]。当连续体中状态密度与能量无关的情况下证明了这种不敏感性。当连续体中的状态密度是能量的阶梯函数时，我们研究相反的极限。由于状态密度的这种逐步行为，驱动兴奋的水平的衰减速率在某些时刻t_0的时间函数会跳跃作为时间的函数。我们利用了以下事实：t <t_0和t> t_0处的分析解决方案已知。我们表明，当T_0与过渡时间相当时，衰减进入生存概率。
A remarkable feature of the Landau-Zener transition is insensitivity of the survival probability to the decay rate, of the excited state. Namely, the probability for a particle, which is initially in the ground state, to remain in the same state is insensitive to decay, which is due to e.g. coupling to continuum [V. M. Akulin and W. P. Schleich, Phys. Rev. A 46, 4110 (1992)]. This insensitivity was demonstrated for the case when the density of states in the continuum is energy-independent. We study the opposite limit when the density of states in the continuum is a step-like function of energy. As a result of this step-like behavior of the density of states, the decay rate of a driven excited level experiences a jump as a function of time at certain moment t_0. We take advantage of the fact that the analytical solution at t<t_0 and at t>t_0 is known. We show that the decay enters the survival probability when t_0 is comparable to the transition time.
