Gated coherent exchange between magnons (spin excitations) in a magnetic sphere (YIG) and photons in a microwave resonator of an electromagnonic device.
Gated coherent exchange between magnons (spin excitations) in a magnetic sphere (YIG) and photons in a microwave resonator of an electromagnonic device.
Image courtesy of Argonne National Laboratory

The Science

People swing through gates every day as they enter and exit gardens, parks, or subways. Electronics have gates, too, but they operate at high speed to control the flow of information. Researchers recently demonstrated fast gate control for a novel information processing platform called electromagnonics. This gate control method couples magnons (electron spin motions in magnetic materials), whose frequencies are highly tunable, and photons in a microwave resonator. The research created a fast and uniform modulation (gating) technique on a magnetic material, yttrium iron garnet. This allowed the scientists to control the transfer of information between the photons and magnons in real time.

The Impact

This research combining magnons and photons as carriers is an example of scientists’ recent work to bring together different types of carriers for information processing. These hybrid systems could allow for new applications that are not possible with a single information carrier. Most importantly, the electronmagnonic gate in this new system can be operated at a high speed to maintain signal coherence during information transfer. This discovery could lead to a new generation of electronmagnonic devices for fast switching and low-power computing. In addition, if cooled to low enough temperatures, this fast gate control method could have a role in quantum computingnetworking, and sensing.

Summary

Coherent gate operation is a long sought-after goal in "electromagnonics" platform – hybridization of electromagnetic waves and magnonic spin excitations – as it is critical for realizing signal processing in real time. However, the lack of tunability of the magnon-microwave photon coupling strength can make it extremely challenging to achieve any control of information gating. In this work performed at the Center for Nanoscale Materials, a Department of Energy Office of Science user facility, the researchers achieved coherent gate operation by introducing a novel modulation technique of the magnon resonance using the ferromagnetic material yttrium iron garnet . Their gate design ensures, for the first time, a fast response time to the control pulses. Such a fast response allows control of the on/off and duration of the magnon-photon interaction, enabling the realization of a series of coherent gated dynamics. Using this novel gating design, the researchers were able to rapidly switch between the magnonic and photonic states on time scale of 10 to 100 nanoseconds, much shorter than the magnon or photon lifetimes.

This demonstration points to a new direction for hybrid magnonics. In the past, hybrid magnonics have  been restricted to only static spectroscopic studies. Importantly, the demonstrated method is fully compatible with cryogenic temperatures. This means it not only works in the classical regime, but can also be readily applied to quantum operations, opening new opportunities for hybrid magnonic-based signal processing in quantum information systems.

Contact

Xu Han
Argonne National Laboratory
xu.han@anl.gov   

Funding

Work performed at the Center for Nanoscale Materials, a Department of Energy (DOE) Office of Science user facility, was supported by the DOE Office of Science,  Office of Basic Energy Sciences. Work was also supported by the U.S. Army Research Lab; U.S. Army Research Office; the U.S. Air Force Office of Scientific Research; the National Science Foundation; and the David and Lucile Packard Foundation.

Publications

Xu, J., et al., Coherent gate operations in hybrid magnonicsPhysical Review Letters 126, 207202 (2021). [DOI: 10.1103/PhysRevLett.126.207202]

Related Links

Opening the Gate to the Next Generation of Information Processing, Argonne National Laboratory Press release

Pivotal Discovery in Quantum and Classical Information Processing, Argonne National Laboratory Press Release