Salcedo-Gallo Juan S, Burgelman Michiel, Flynn Vincent P, Carney Alexander S, Hamdan Majd, Gerg Tunmay, Smallwood Daniel C, Viola Lorenza, Fitzpatrick Mattias
Thayer School of Engineering, Dartmouth College, 15 Thayer Drive, Hanover, NH, 03755, USA.
Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH, 03755, USA.
Nat Commun. 2025 Aug 5;16(1):7193. doi: 10.1038/s41467-025-62620-1.
Achieving and controlling non-reciprocity in engineered photonic structures is of fundamental interest in science and engineering. Here, we introduce a tunable, non-Hermitian, nonlinear microwave dimer designed to precisely implement phase-non-reciprocal hopping dynamics between two spatially separated cavities at room temperature. Our system incorporates simple components such as three-dimensional microwave cavities, unidirectional amplifiers, digital attenuators, and a digital phase shifter. By dividing the energy transfer into forward and backward paths, our platform enables precise control over the amplitude and phase of the propagating signals in each direction. Through a combination of theoretical and numerical analysis, we model the dynamics of the system under different operating conditions, including a parameter regime where the gain not only compensates for but significantly exceeds the inherent loss. Our model quantitatively reproduces the observed weak-drive transmission spectra, the amplitude and frequency of self-sustained limit cycles, and the phase locking synchronization effect between the limit cycle and an external microwave tone. Our results may have implications in areas ranging from sensing and synthetic photonic materials to neuromorphic computing and quantum networks, while providing new insight into the interplay between non-Hermitian and nonlinear dynamics.
在工程光子结构中实现并控制非互易性是科学与工程领域的基本研究兴趣所在。在此，我们介绍一种可调谐、非厄米、非线性微波二聚体，其设计目的是在室温下精确实现两个空间分离的腔之间的相位非互易跳跃动力学。我们的系统包含诸如三维微波腔、单向放大器、数字衰减器和数字移相器等简单组件。通过将能量传输分为正向和反向路径，我们的平台能够精确控制每个方向上传播信号的幅度和相位。通过理论分析与数值分析相结合，我们对系统在不同工作条件下的动力学进行建模，包括增益不仅补偿固有损耗而且显著超过固有损耗的参数区域。我们的模型定量再现了观测到的弱驱动传输光谱、自持极限环的幅度和频率，以及极限环与外部微波音调之间的锁相同步效应。我们的结果可能在从传感与合成光子材料到神经形态计算和量子网络等领域产生影响，同时为非厄米动力学与非线性动力学之间的相互作用提供新的见解。
