Magnetic order induced chiral phonons in a ferromagnetic Weyl semimetal

Abstract

Chiral phonons are vibrational modes in a crystal that possess a well-defined handedness or chirality, typically found in materials that lack inversion symmetry. Here we report the discovery of chiral phonon modes in the kagome ferromagnetic Weyl semimetal Co3Sn2S2, a material that preserves inversion symmetry but breaks time-reversal symmetry. Using helicity-resolved magneto-Raman spectroscopy, we observe the spontaneous splitting of the doubly degenerate in-plane Eg modes into two distinct chiral phonon modes of opposite helicity when the sample is zero-field cooled below the Curie temperature, in the absence of an external magnetic field. As we sweep the out-of-plane magnetic field, this Eg phonon splitting exhibits a well-defined hysteresis loop directly correlated with the material's magnetization. The observed spontaneous splitting reaches up to 1.27 cm-1 at low temperatures, progressively diminishes with increasing temperature, and completely vanishes near the Curie temperature. Our findings highlight the role of the magnetic order in inducing chiral phonons, paving the way for novel methods to manipulate chiral phonons through magnetization and vice versa. Additionally, our work introduces new possibilities for controlling chiral Weyl fermions using chiral phonons.

References in corpus (24)

• Valley Dependent Optoelectronics from Inversion Symmetry Breaking
• Polarized phonons carry the missing angular momentum in femtosecond demagnetization
• Truly chiral phonons in α-HgS
• Orbital magnetic moments of phonons
• Chiral phonons probed by X rays
• Terahertz electric-field driven dynamical multiferroicity in SrTiO${}_3$
• Large effective magnetic fields from chiral phonons in rare-earth halides
• 33% Giant Anomalous Hall Current Driven by both Intrinsic and Extrinsic Contributions in Magnetic Weyl Semimetal Co3Sn2S2
• Phononic Switching of Magnetization by the Ultrafast Barnett Effect
• Chirality selective magnon-phonon hybridization and magnon-induced chiral phonons in a layered zigzag antiferromagnet
• Chiral Phonon Induced Spin-Polarization
• Chiral Phonons with Giant Magnetic Moments in a Topological Crystalline Insulator
• Detecting Chiral Magnetic Effect by Lattice Dynamics
• Chiral phonons and pseudo-angular momentum in non-symmorphic systems
• Giant effective magnetic moments of chiral phonons from orbit-lattice coupling
• On the anisotropies of magnetization and electronic transport of magnetic Weyl semimetal Co3Sn2S2
• Unconventional interlayer exchange coupling via chiral phonons in synthetic magnetic oxide heterostructures
• Spin Excitations and Spin Wave Gap in the Ferromagnetic Weyl Semimetal Co${}_3$Sn${}_2$S${}_2$
• Weyl phonons in chiral crystals
• Lattice dynamics with molecular Berry curvature: chiral optical phonons
• Frequency splitting of chiral phonons from broken time reversal symmetry in CrI${}_3$
• Unusual exchange couplings and intermediate temperature Weyl state in Co3Sn2S2
• Observation of a phase transition within the domain walls of ferromagnetic Co3Sn2S2
• Adiabatic dynamics of coupled spins and phonons in magnetic insulators

Cited by in corpus (12)

• Kagome metals
• Magnetic switching of phonon angular momentum in a ferrimagnetic insulator
• Comprehensive Study of Phonon Chirality under Symmetry Constraints
• Discovery of terahertz-frequency orbitally-coupled magnons in a kagome ferromagnet
• Catalogue of chiral phonon materials
• Magnetic Signature of Chiral Phonons Revealed by Neutron Spectroscopy in Ferrimagnetic Fe${}_{1.75}$Zn${}_{0.25}$Mo${}_3$O${}_8$
• Anomalous phonon magnetic moments
• Dynamical Orbital Angular Momentum Induced by Circularly Polarized Phonons
• Anisotropic electron-phonon coupling and chiral phonons in van der Waals room temperature ferromagnet Fe${}_5$GeTe${}_2$
• General ab initio framework for electronic-order-induced lattice-dynamics symmetry breaking
• Raman spectroscopy of van der Waals topological magnet GdGaI
• Pseudo-chiral phonon splitting from octupolar magnetic order