Intrinsic spin of elastic waves

  title={Intrinsic spin of elastic waves},
  author={Yang Long and Jie Ren and Hong Chen},
  journal={Proceedings of the National Academy of Sciences},
  pages={9951 - 9955}
Significance Spin unveils the fundamental geometrical and topological properties of waves. Massive studies have shown that the circularly polarized transverse wave can carry nontrivial spin density and thus possess quantum spin Hall effect. However, the spin nature of the longitudinal wave still lacks research. Here, based on the elastic wave platform, we show that the longitudinal wave can carry unique spin angular momentum due to its special spin–orbit coupling, and, importantly, the mixed… 

Figures from this paper

Observation of elastic spin with chiral meta-sources
Directional routing of one-way classical wave has raised tremendous interests about spin-related phenomena in topological metamaterials. This sparks specifically the elastic wave study of
Electromagnetic spin in a generic field
Electromagnetic spins, including longitudinal and transverse ones, have been playing important roles in light-matter interactions. We formulate a unified equation here to uncover the physical origins
Extraordinary spin in a generic electromagnetic field
Electromagnetic spins, including longitudinal and transverse ones, have been playing important roles in light-matter interactions, leading to many intriguing phenomena and applications. Previously,
Observation of elastic spin with chiral meta-sources.
The unidirectional routing of chiral elastic waves is observed, the different elastic spins along different directions are characterized, and the spin-momentum locking in broad frequency ranges is demonstrated.
Spin photonics: from transverse spin to photonic skyrmions
Abstract Spin angular momentum associated with circular polarization is a fundamental and important aspect of photons both in classical and quantum optics. The interaction of this optical spin with
Field theory spin and momentum in water waves
The canonical spin and momentum in water waves are revealed and directly observe these fundamental relativistic field-theory properties as microscopic mechanical properties of particles in a classical wave system.
Extraordinary transverse spin: hidden vorticity of the energy flow and momentum distributions in propagating light fields
  • A. Bekshaev
  • Physics
    International Conference on Correlation Optics
  • 2021
Spatially inhomogeneous fields of electromagnetic guided modes exhibit a complex of extraordinary dynamical properties such as the polarization-dependent transverse momentum, helicity-independent
Real spin angular momentum and acoustic spin torque in a topological phononic crystal
The topological one-way waveguide mode of the acoustic wave has recently been demonstrated in various meta-structure systems. Here, we show that in a topological phononic crystal with a
Elastic Spin and Orbital Angular Momenta
Motivated by recent theoretical and experimental interest in the spin and orbital angular momenta of elastic waves, we revisit canonical wave momentum, spin, and orbital angular momentum in isotropic
Spin and orbital angular momenta of acoustic beams
We analyze spin and orbital angular momenta in monochromatic acoustic wave fields in a homogeneous medium. Despite being purely longitudinal (curl-free), inhomogeneous acoustic waves generically


Detecting the phonon spin in magnon–phonon conversion experiments
Recent advances in the emerging field of magnon spintronics have stimulated renewed interest in phenomena involving the interaction between spin waves, the collective excitations of spins in magnetic
Spin-orbit interactions of light
This Review article provides an overview of the fundamental origins and important applications of the main spin–orbit interaction phenomena in modern optics that play a crucial role at subwavelength
Geometrodynamics of spinning light
The semiclassical evolution of spinning particles has recently been re-examined in condensed matter physics, high-energy physics, and optics, resulting in the prediction of the intrinsic spin Hall
Topological origin of equatorial waves
A topological origin is shown for two well-known equatorially trapped waves, the Kelvin and Yanai modes, owing to the breaking of time-reversal symmetry by Earth's rotation, which demonstrates that ocean and atmospheric waves share fundamental properties with topological insulators and that topology plays an unexpected role in Earth's climate system.
Internal flows and energy circulation in light beams
We review optical phenomena associated with the internal energy redistribution which accompany propagation and transformations of monochromatic light fields in homogeneous media. The total energy
Measuring the transverse spin density of light.
The longitudinal electric component of Belinfante's elusive spin momentum density is determined, a solenoidal field quantity often referred to as "virtual" in this work.
Topological Phononic Crystals with One-Way Elastic Edge Waves.
A new type of phononic crystals with topologically nontrivial band gaps for both longitudinal and transverse polarizations, resulting in protected one-way elastic edge waves, which could potentially lead to the design of a novel class of surface wave devices that are widely used in electronics, telecommunication, and acoustic imaging.
Spin-Orbit Coupling for Photons and Polaritons in Microstructures
We use coupled micropillars etched out of a semiconductor microcavity to engineer a spin-orbit Hamiltonian for photons and polaritons in a microstructure. The coupling between the spin and orbital
From transverse angular momentum to photonic wheels
This Progress Article details the latest achievements and underlying principles of light carrying transverse spin.The capabilities and future applications of this young yet already advanced field are
Spin-Optical Metamaterial Route to Spin-Controlled Photonics
It is shown that polarization-controlled optical modes of metamaterials arise where the spatial inversion symmetry is violated, and the emerged spin-split dispersion of spontaneous emission originates from the spin-orbit interaction of light, generating a selection rule based on symmetry restrictions in a spin-optical meetamaterial.