Programmable Integrated Magneto-Phononic Circuits

声子，声波的准粒子，是现代通信技术中不可或缺的资源，因为它们与任何其他系统都具有普遍的耦合性。此外，声子以中等速度传播，大约比光速慢10万倍。这使得千兆赫频率设备小型化到芯片大小。磁系统在完全相同的频域中表现出自旋波激励，因此，非常适合通过磁致伸缩与声波耦合。在这个项目中，我们开发了高度集成的可编程和可扩展电路，其中声子的传播可以通过精确设计的磁性薄膜和图案来操纵甚至编程。为此，我们将我们互补的理论和实验专业知识结合起来，开发了一个完整的电路元件工具箱，用于设计集成磁声子电路。本项目解决了三个对基本理解和应用至关重要的主要目标和研究问题：(1)发展理论和实验方法来建模，设计和制造磁声子集成电路。为此，我们将(i)在一个共同的平台上统一磁性和声子系统的建模方法，（ii）结合声子电路和磁性薄膜的纳米制造技术，以及（iii）通过射频光谱验证设计和制造的磁声子电路。(2)磁薄膜系统与色散工程声子波导的磁声子耦合研究。(3)采用磁阵列实现集成和可编程原型设备，例如用于射频应用的隔离器和环行器。在项目的每个阶段，新的理论方法和实验技术将被开发，这不仅解决了重要的基本问题。此外，它为新型磁声子电路及其巨大的潜在前景奠定了基础，甚至与光学可寻址自旋系统或量子发射器相结合，具有更深远的应用。

Phonons, the quasi-particles of sound waves represent an indispensable resource in modern communication technologies because of their universal coupling to literally any other system. Moreover, phonons propagate with moderate velocities which are approximately 100000-times slower than the speed of light. This enables miniaturization of gigahertz frequency devices to the size of a chip. Magnetic systems exhibit spin-wave excitations in exactly the same frequency domain and, thus, are ideally suited to couple to sound waves via magnetostriction.In this project, we develop highly integrated programmable and scalable circuits, in which the propagation of phonons can be manipulated and even programmed by precisely engineered magnetic thin films and patterns. To this end, we bundle our complementary theoretical and experimental expertise and develop a complete toolbox of circuit elements for the design of integrated magneto-phononic circuits. This project addresses three major objective and research questions which are crucial for the fundamental understanding and for applications:(1) Development of theoretical and experimental methods to model, design and fabricate magneto-phononic integrated circuits. To this end, we will (i) unify modelling methods for magnetic and phononic systems on a common platform, (ii) combine nanofabrication techniques of phononic circuits and magnetic thin films, and (iii) validate the designed and fabricated magneto-phononic circuits by radio frequency spectroscopy.(2) Investigation of the magneto-phononic coupling between magnetic thin film systems and dispersion-engineered phononic waveguides.(3) Realization of integrated and programmable prototype devices employing magnetic arrays, e.g. for isolators and circulators radio frequency applications.At each stage of the project, new theoretical approaches and experimental techniques will be developed, which not only address important fundamental questions. Moreover, it lays the foundation for novel magneto-phononic circuits and their vast potential promise even more far-reaching applications in combination with for instance optically addressable spin systems or quantum emitters.