arXiv subjects

Y. M. Blanter

Publications and source records attributed to Y. M. Blanter.

6 recordsLinked to original sources

arXiv2023

Observation and control of hybrid spin-wave-Meissner-current transport modes

Superconductors are materials with zero electrical resistivity and the ability to expel magnetic fields known as the Meissner effect. Their dissipationless diamagnetic response is central to magnetic levitation and circuits such as quantum interference devices. Here, we use superconducting diamagnetism to shape the magnetic environment governing the transport of spin waves - collective spin excitations in magnets that are promising on-chip signal carriers - in a thin-film magnet. Using diamond-based magnetic imaging, we observe hybridized spin-wave-Meissner-current transport modes with strongly altered, temperature-tunable wavelengths. We extract the temperature-dependent London penetration depth from the wavelength shifts and realize local control of spin-wave refraction using a focused laser. Our results demonstrate the versatility of superconductor-manipulated spin-wave transport and have potential applications in spin-wave gratings, filters, crystals and cavities.

cond-mat.mes-hall↗

arXiv2023

Soft Magnons in Anisotropic Ferromagnets

We discuss spin-wave transport in anisotropic ferromagnets with an emphasis on the zeroes of the band edges as a function of a magnetic field. An associated divergence of the magnon spin should be observable by enhanced magnon conductivities in non-local experiments, especially in two-dimensional ferromagnets.

cond-mat.mes-hall↗

arXiv2021

Roadmap on Spin-Wave Computing

Magnonics is a field of science that addresses the physical properties of spin waves and utilizes them for data processing. Scalability down to atomic dimensions, operations in the GHz-to-THz frequency range, utilization of nonlinear and nonreciprocal phenomena, and compatibility with CMOS are just a few of many advantages offered by magnons. Although magnonics is still primarily positioned in the academic domain, the scientific and technological challenges of the field are being extensively investigated, and many proof-of-concept prototypes have already been realized in laboratories. This roadmap is a product of the collective work of many authors that covers versatile spin-wave computing approaches, conceptual building blocks, and underlying physical phenomena. In particular, the roadmap discusses the computation operations with Boolean digital data, unconventional approaches like neuromorphic computing, and the progress towards magnon-based quantum computing. The article is organized as a collection of sub-sections grouped into seven large thematic sections. Each sub-section is prepared by one or a group of authors and concludes with a brief description of the current challenges and the outlook of the further development of the research directions.

physics.app-ph↗

arXiv2019

Light-driven ultrafast phonomagnetism

Exciting atomic oscillations with light is a powerful technique to control the electronic properties of materials, leading to remarkable phenomena such as light-induced superconductivity and ultrafast insulator to metal transitions. Here we show that light-driven lattice vibrations can be utilised to encode efficiently spin information in a magnetic medium. Intense mid-infrared electric field pulses, tuned to resonance with a vibrational normal mode of antiferromagnetic DyFeO3, drive the emergence of long-living weak ferromagnetic order. Light-driven phonon displacements promptly lower the energy barrier separating competing magnetic states, allowing the alignment of spins to occur within a few picoseconds, via non-equilibrium dynamics of the magnetic energy landscape.

cond-mat.str-el↗

arXiv2018

Selection rules for cavity-enhanced Brillouin light scattering from magnetostatic modes

We experimentally identify the magnetostatic modes active for Brillouin light scattering in the optical whispering gallery modes of a yttrium iron garnet sphere. Each mode is identified by magnetic field dispersion of ferromagnetic-resonance spectroscopy and coupling strength to the known field distribution of the microwave drive antenna. Our optical measurements confirm recent predictions that higher-order magnetostatic modes can also generate optical scattering, according to the selection rules derived from the axial symmetry. From this we summarize the selection rules for Brillouin light scattering. We give experimental evidence that the optomagnonic coupling to non-uniform magnons can be higher than that of the uniform Kittel mode.

cond-mat.mes-hall↗

arXiv2015

Optomechanical coupling between a multilayer graphene mechanical resonator and a superconducting microwave cavity

The combination of low mass density, high frequency, and high quality-factor of mechanical resonators made of two-dimensional crystals such as graphene make them attractive for applications in force sensing/mass sensing, and exploring the quantum regime of mechanical motion. Microwave optomechanics with superconducting cavities offers exquisite position sensitivity and enables the preparation and detection of mechanical systems in the quantum ground state. Here, we demonstrate coupling between a multilayer graphene resonator with quality factors up to 220,000 and a high-$\textit{Q}$ superconducting cavity. Using thermo-mechanical noise as calibration, we achieve a displacement sensitivity of 17 fm/$\sqrt{\text{Hz}}$. Optomechanical coupling is demonstrated by optomechanically induced reflection (OMIR) and absorption (OMIA) of microwave photons. We observe 17 dB of mechanical microwave amplification and signatures of strong optomechanical backaction. We extract the cooperativity $C$, a characterization of coupling strength, quantitatively from the measurement with no free parameters and find $C=8$, promising for the quantum regime of graphene motion.

cond-mat.mes-hall↗