Chemical Physics Theory Group, Department of Chemistry, University of Toronto, 80 Saint George St., Toronto, Ontario M5S 3H6, Canada.
Institute of Industrial Science, University of Tokyo, Komaba 4-6-1, Meguro, Tokyo 153-8505, Japan.
J Chem Phys. 2014 Mar 28;140(12):124709. doi: 10.1063/1.4869519.
We study Landau-Zener transitions between two states with the addition of a shared discretized continuum. The continuum allows for population decay from the initial state as well as indirect transitions between the two states. The probability of nonadiabatic transition in this multichannel model preserves the standard Landau-Zener functional form except for a shift in the usual exponential factor, reflecting population transfer into the continuum. We provide an intuitive explanation for this behavior assuming individual, independent transitions between pairs of states. In contrast, the ground state survival probability at long time shows a novel, non-monotonic, functional form with an oscillatory behavior in the sweep rate at low sweep rate values. We contrast the behavior of this open-multistate model to other generalized Landau-Zener models incorporating an environment: the stochastic Landau-Zener model and the dissipative case, where energy dissipation and thermal excitations affect the adiabatic region. Finally, we present evidence that the continuum of states may act to shield the two-state Landau-Zener transition probability from the effect of noise.
我们研究了在添加共享离散连续统的情况下，两个状态之间的 Landau-Zener 跃迁。连续统允许初始状态的种群衰减，以及两个状态之间的间接跃迁。在这个多通道模型中，非绝热跃迁的概率除了通常的指数因子的移动之外，保留了标准的 Landau-Zener 函数形式，反映了种群转移到连续统中。我们假设个体之间的独立跃迁来对这种行为进行直观解释。相比之下，长时间的基态存活概率表现出一种新颖的、非单调的函数形式，在低扫掠率值下，扫掠率具有振荡行为。我们将这个开放多态模型的行为与其他包含环境的广义 Landau-Zener 模型进行对比：随机 Landau-Zener 模型和耗散情况，其中能量耗散和热激发会影响绝热区域。最后，我们提供了证据表明，状态的连续统可能会保护两态 Landau-Zener 跃迁概率免受噪声的影响。
