Electric field control of interaction between magnons and quantum spin defects

Abstract

The nanoscale magnetic field of magnons has emerged as a promising resource for coherently driving qubits such as quantum spin defects (QSD) and developing versatile probes for magnetism and other types of quantum matter. Tuning this coupling via electric field would provide a path to address the outstanding challenges of enhancing QSD-based sensing of electric fields and locally manipulating QSD qubits with minimal power. Here, we demonstrate a new approach to such electric field tuning using a ferromagnet-ferroelectric hybrid multiferroic film integrated with nitrogen-vacancy (NV) center spins. Combining NV-spin relaxometry with ferromagnetic resonance measurements, we reveal that the ferroelectric polarization controls the magnetic anisotropy, which tunes the magnon-generated fields at the NVs. Flipping the ferroelectric polarization changes NV-spin relaxation rate by 400%, which could be further enhanced by three orders of magnitude by nanopatterning the ferromagnets. Our results offer possibilities of realizing improved NV-sensing of electric fields, electric-field-tunable quantum spintronic devices, and magnon/spin probes of the multiferroic order and quantum materials.

Scanning Spin Probe Based on Magnonic Vortex Quantum Cavities

“…In addition to photons, the solid state offers a wide variety of bosonic excitations that can be emitted or absorbed such as, e.g., quantized spin waves or magnons. − In what follows, we will use g to denote both the spin–photon and spin–magnon coupling. Magnonic cavities could be used to perform spin qubit readout or to mediate spin–spin interactions, − offering the advantage of increasing the coupling by operating at reduced wavelengths (compared to electromagnetic resonators of the same frequency). This is possible since spin wave modulation is limited only by the lattice constant of the ferromagnet, allowing the downsizing to the nanometer range.…”

Mechanical Control of Polaritonic States in Lead Halide Perovskite Phonons Strongly Coupled in THz Microcavity

“…Strong light-matter interactions of quasi-particles, such as excitons, phonons, and surface polaritons, in a microcavity induces the formation of polaritons, which opens up exciting research fields, such as Bose–Einstein condensation, , polariton lasers, , all-optical circuits, , and quantum devices. , When the light–matter interaction is under a strong coupling regime (i.e., when the coupling strength exceeds the dissipation loss), the energy exchange between the quasi-particle and the cavity leads to vacuum field Rabi splitting, exhibiting an anticross behavior. , Quantum energy states in polariton systems have attracted particular interest owing to the potential of quantum information processing with fast switching possibilities, relatively strong nonlinear response, and low power to perform logical operations. , Control over quantum states, such as their initialization, operation, and readout, has been achieved through optical pulse excitation at multiple energy levels. − Conversely, microcavity polaritons incorporated with tunable environments can add additional degrees of freedom for their efficient control, for instance, through electrical fields, − magnetic fields, − and mechanical perturbations. − …”

Greatly Enhanced Emission from Spin Defects in Hexagonal Boron Nitride Enabled by a Low-Loss Plasmonic Nanocavity

“…Compared to the reports above, our configuration processes the following unique advantages: (1) a much smaller laser power required for achieving effective sensing, which avoids the detrimental effects of high driving powers; (2) a much higher spatial resolution as defined by the silver nanocube dimension (∼100 nm) and an extremely small separation distance between the probing spin and material of interest (3 nm). In the case of sensing magnetic excitations, 57 this sample−probe distance not only improves the strength of stray magnetic fields but also determines the wavelength of the excitations that couple with the spin transition. Furthermore, measuring stray magnetic fields emanating from magnetic materials at a close distance of ∼3 nm enables advanced probes for previously unexplored phenomena.…”