单能级Fano-Anderson模型中连续介质的束缚态

Broadband Parametric Downconversion as a Discrete-Continuum Fano Interaction

We introduce a theoretical framework based on Fano's theory of discrete-continuum interactions to analyze the quantum dynamics of broadband parametric downconversion (PDC) in the few-pump-photon regime of nonlinear quantum nanophotonics. Applying this unified analytic approach to 1D $χ^{(2)}$-nonlinear waveguides, we find a host of remarkable dynamical features due to the coupling of a discrete pump state to the signal continuum, from unit-efficiency (i.e., complete) downconversion when the coupling is dissipative, to Rabi-like oscillations with sub-exponential decay when it is dispersive. The…

Transition from Lorentz to Fano Spectral Line Shapes in Non-Relativistic Quantum Electrodynamics

Spectroscopic signatures associated with symmetric Lorentzian and asymmetric Fano line shapes are ubiquitous. Distinct features of Fano resonances in contrast with conventional symmetric resonances have found several applications in photonics such as optical switching, sensing, lasing, and nonlinear and slow-light devices. Therefore, it is important to have control over the generation of these resonances. In this work, we show through ab initio simulations of coupled light-matter systems that Fano interference phenomena can be realized in a multimode photonic environment by strong coupling to …

连续束缚波与离散无限运动态的“特殊”共存

"Paradoxical" coexistence of continuum of 'bound' waves and discrete set of unlimited motion states

我们结合了两个显著的现象：共振隧穿和安德森局域化。这导致了与通常概念相反的意外频谱。通过势共振隧穿陷阱在整个坐标轴上混沌分布的量子系统证明了这一点。相应的频谱包含连续的“束缚”状态（安德森的本地化）和离散的隧道共振无限波传播。这与通常的散射态为连续态和离散态的情况不同。

Engineering zero modes, Fano resonance and Tamm surface states of 'bound states in the gapped continuum'

In this article, we developed a generalized coupled-mode theory for mixing an isolated state with the gapped continuum to unify the engineering mechanism of gap-protected zero modes, Fano resonance and Tamm surface states, even though those phenomena are diverse in numerous branches of physics and optics. By tuning the on-site potential and coupling strength of/with the isolated state, we found the operating characteristics from zero modes, Fano resonance and to Tamm modes, with explicitly demonstrating their localization, transmission spectra and distinct evolution dynamics of the 'bound stat…

用侵入连续统调谐Fano共振

Tuning the Fano Resonance with an Intruder Continuum

通过实验和理论相结合，我们建立了实现强调谐的法诺共振（FR）的可能性，通过允许他们通常的两个路径的几何形状干扰一个额外的，“入侵者”，连续。由于这个入侵者的耦合强度是不同的，我们预测强烈的调制的共振线的形状，至少在原则上，可能会超过原来的FR本身的振幅。为了证明这种现象的概念演示，我们构建了一个纳米级的干涉仪从非局域耦合量子点接触，并利用其独特的功能的状态密度来实现入侵者。入侵者耦合的外部控制是通过施加的磁场，在存在的情况下，我们证明了预测的失真的FR。谐振控制的一般计划应广泛适用于各种波为基础的系统，开辟了新的应用领域，如化学和生物传感和安全通信的可能性。

Quantum decay in a topological continuum

The quantum mechanical decay of two or more overlapped resonances in a common continuum is largely influenced by Fano interference, leading to important phenomena such as the existence of bound states in the continuum, fractional decay and quiescent dynamics for single particle decay, and signature of particle statistics in the many-body quantum decay. An overlooked yet essential requirement to observe Fano interference is time reversal symmetry of the bath. Here we consider multilevel quantum decay in a bath sustaining unidirectional (chiral) propagating states, such as in quantum Hall or in …

平坦带的Fano格解缠

Detangling Flat Bands into Fano Lattices

周期晶格中的宏观简并平带（FB）具有紧凑的局域态，这些局域态是由于相消干涉和局域对称性而出现的。干涉在平带态（FBS）的存在和波传播的Fano共振的出现之间提供了深刻的联系。我们引入通用的变换去缠结FBS和色散状态到晶格的Fano缺陷。逆变换，我们生成一个连续的FB模型。我们的程序使我们能够系统地处理扰动，如无序和解释的出现依赖于能量的本地化长度缩放的法诺共振。

连续介质中束缚态的光频调谐

Tunable Bound States in Continuum by Optical Frequency

我们证明了在强单色光场作用下，含有两个杂质的一维量子线中存在连续可调束缚态。我们发现，除了由杂质发射的电子波函数之间的几何干涉引起的普通BIC外，还存在一种由两个光学跃迁通道之间的Fano干涉引起的新型BIC。在这两种情况下，BIC可以通过调谐辐射场的频率来实现。

Fano相干产生的能量学

Energetics of Fano coherence generation

本文提出V型三能级量子系统，利用Kirkwood-Dirac拟概率分布的非正定性认证Fano相干产生的量子本质，并分析其可提取功与热力学效率。

一维无公度光晶格中迁移率边的预测：一个精确可解的安德森局域化模型

Predicted mobility edges in one-dimensional incommensurate optical lattices: An exactly solvable model of Anderson localization

利用超越最小近邻紧束缚模型的指数短程跳跃研究了一维无公度晶格中非相互作用量子粒子的局域化性质。在这个模型中，能量依赖的迁移率边缘的解析预测和验证的数值计算。然后将结果映射到连续薛定谔方程，得到了局域化相图和基态能量相关迁移率边的近似解析表达式。