Litvinenko K L, Le Nguyen H, Redlich B, Pidgeon C R, Abrosimov N V, Andreev Y, Huang Zhiming, Murdin B N
Department of Physics, Advanced Technology Institute, University of Surrey, Guildford, GU2 7XH, UK.
FELIX Laboratory, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands.
Nat Commun. 2021 Jan 19;12(1):454. doi: 10.1038/s41467-020-20534-0.
The ordinary Fano effect occurs in many-electron atoms and requires an autoionizing state. With such a state, photo-ionization may proceed via pathways that interfere, and the characteristic asymmetric resonance structures appear in the continuum. Here we demonstrate that Fano structure may also be induced without need of auto-ionization, by dressing the continuum with an ordinary bound state in any atom by a coupling laser. Using multi-photon processes gives complete, ultra-fast control over the interference. We show that a line-shape index q near unity (maximum asymmetry) may be produced in hydrogenic silicon donors with a relatively weak beam. Since the Fano lineshape has both constructive and destructive interference, the laser control opens the possibility of state-selective detection with enhancement on one side of resonance and invisibility on the other. We discuss a variety of atomic and molecular spectroscopies, and in the case of silicon donors we provide a calculation for a qubit readout application.
普通的法诺效应发生在多电子原子中，且需要一个自电离态。有了这样一个态，光电离可以通过相互干涉的路径进行，并且在连续谱中会出现特征性的不对称共振结构。在此我们证明，通过用耦合激光将任何原子中的普通束缚态与连续谱相结合，无需自电离也可以诱导出法诺结构。利用多光子过程能够实现对干涉的完全、超快速控制。我们表明，用相对较弱的光束就可以在类氢硅施主中产生接近1（最大不对称性）的线形指数q。由于法诺线形同时存在相长干涉和相消干涉，激光控制开启了态选择性探测的可能性，在共振的一侧增强而在另一侧不可见。我们讨论了各种原子和分子光谱学，并且在硅施主的情况下，我们提供了一个用于量子比特读出应用的计算。
