Building Blocks for Magnon Optics: Emission and Conversion of Short Spin Waves

Abstract

Magnons have proven to be a promising candidate for low-power wave-based computing. The ability to encode information not only in amplitude but also in phase allows for increased data transmission rates. However, efficiently exciting nanoscale spin waves for a functional device requires sophisticated lithography techniques and therefore, remains a challenge. Here, we report on a method to measure the full spin wave isofrequency contour for a given frequency and field. A single antidot within a continuous thin film excites wave vectors along all directions within a single excitation geometry. Varying structural parameters or introducing Dzyaloshinskii–Moriya interaction allows the manipulation and control of the isofrequency contour, which is desirable for the fabrication of future magnonic devices. Additionally, the same antidot structure is utilized as a multipurpose spin wave device. Depending on its position with respect to the microstrip antenna, it can either be an emitter for short spin waves or a directional converter for incoming plane waves. Using simulations we show that such a converter structure is capable of generating a coherent spin wave beam. By introducing a short wavelength spin wave beam into existing magnonic gate logic, it is conceivable to reduce the size of devices to the micrometer scale. This method gives access to short wavelength spin waves to a broad range of magnonic devices without the need for refined sample preparation techniques. The presented toolbox for spin wave manipulation, emission, and conversion is a crucial step for spin wave optics and gate logic.

Interference patterns of propagating spin wave in spin-Hall oscillator arrays

“…Furthermore, the wavelength of the propagation can be reduced to 100 nm using a straightforward lithography process that is compatible with CMOS technology. [33][34][35][36] Of notable significance is the ability of propagating spin waves to induce mutual synchronization over micron-scale distances, which holds considerable importance for emerging spin-wave computing platforms. [37][38][39] Yet, the study of the interference pattern between spin-torque oscillators has not been addressed so far.…”

Spin‐Wave Optics in YIG Realized by Ion‐Beam Irradiation

“…A major motivation behind magnonics research is to replicate the functionality of bulky optical components in chip-scale devices that are amenable to integration with microelectronic circuitry. [1][2][3][4][5][6][7] This way, the functionality of coherent optical computers could also be cloned in the magnonic domain. Spin waves (SWs) display interference phenomena that resemble that of optical waves, but they offer submicron (possibly sub-100 nm) wavelength and can be launched and detected by electrical means.…”

Néel domain wall as a tunable filter for optically excited magnetostatic waves

“…Developing approaches for controlling SW is essential for bringing magnonic concepts to real applications. Control of SW amplitude, phase, velocity and propagation direction have been demonstrated by introducing various types of magnetic nonuniformity in the SW guiding medium [12][13][14][15][16]. In particular, chiral topological defects such as domain walls (DW) change amplitude and phase of SW passing through them [17][18][19][20][21].…”