Excitation mechanisms using intense lasers are described as being either a multiphoton or tunneling process, based on whether the Keldysh parameter γ is greater than or less than unity. However, the lack of intrinsic connection between these two excitation mechanisms fetters the cognizance of dynamics in strong field ionization under typical experimental conditions. In this paper, quantum tunneling and the multiphoton process are connected by an intuitive picture of wavepacket interference. In this view, the transition from multiphoton resonance to tunneling is recognized as a decoherence process of tunneling electrons. We reveal this decoherence in crystals and gases when the Keldysh parameter decreases. In this process, the characteristics of driving fields, frequent scattering in crystals and localization play an important role. Moreover, once this understanding of multiphoton resonance is obtained, additional means are provided for coherent control in electron excitations. We find that the interference of tunneling electrons leads to novel performances of the transition rate in subcycles, and provides a theoretical method of attosecond-resolved quantum interference control. Our work opens up a new prospect of electron ultrafast control.

使用强激光的激发机制被描述为多光子或隧穿过程，基于 Keldysh 参数γ大于或小于统一。然而，这两种激发机制之间缺乏内在联系限制了对典型实验条件下强场电离动力学的认识。在本文中，量子隧穿和多光子过程通过波包干涉的直观图相联系起来。在这种观点下，从多光子共振到隧穿的转变被认为是隧穿电子的退相干过程。当 Keldysh 参数减小时，我们揭示了晶体和气体中的这种退相干性。在这个过程中，驱动场的特性、晶体中频繁的散射和定位起着重要的作用。此外，一旦获得了对多光子共振的理解，就可以为电子激发中的相干控制提供额外的手段。我们发现隧道电子的干涉导致了亚周期跃迁率的新性能，并提供了阿秒分辨量子干涉控制的理论方法。我们的工作开辟了电子超快控制的新前景。