18 research outputs found
Non-conformal higher spin supercurrents
In four spacetime dimensions there exist two off-shell formulations for the
massless multiplet of superspin , where . These
supersymmetric higher spin gauge theories, known as longitudinal and
transverse, are dual to each other and describe two massless fields of spin
and upon elimination of the auxiliary fields. They
respectively reduce, in the limiting case of , to the linearised actions
for the old minimal and the non-minimal supergravity
theories. Associated with these gauge massless theories are non-conformal
higher spin supercurrent multiplets which we describe. We demonstrate that the
longitudinal higher spin supercurrents are realised in the model for a massive
chiral scalar superfield only if is odd, , with .Comment: 12 pages; V2: typos corrected; V3: published versio
Transverse magneto-optical Kerr effect in subwavelength dielectric gratings
We demonstrate theoretically a large transverse magneto-optical Kerr effect
(TMOKE) in subwavelength gratings consisting of alternating magneto-insulating
and nonmagnetic dielectric nanostripes. The reflectivity of the grating reaches
at the frequencies corresponding to the maximum of the TMOKE response.
The combination of a large TMOKE response and high reflectivity is important
for applications in D imaging, magneto-optical data storage, and magnonics
Rigorous numerical study of strong microwave photon-magnon coupling in all-dielectric magnetic multilayers
We demonstrate theoretically a strong local enhancement of the intensity of
the in-plane microwave magnetic field in multilayered structures made from a
magneto-insulating yttrium iron garnet (YIG) layer sandwiched between two
non-magnetic layers with a high dielectric constant matching that of YIG. The
enhancement is predicted for the excitation regime when the microwave magnetic
field is induced inside the multilayer by the transducer of a stripline
Broadband Ferromagnetic Resonance (BFMR) setup. By means of a rigorous
numerical solution of the Landau-Lifshitz-Gilbert equation consistently with
the Maxwell's equations, we investigate the magnetisation dynamics in the
multilayer. We reveal a strong photon-magnon coupling, which manifests itself
as anti-crossing of the ferromagnetic resonance (FMR) magnon mode supported by
the YIG layer and the electromagnetic resonance mode supported by the whole
multilayered structure. The frequency of the magnon mode depends on the
external static magnetic field, which in our case is applied tangentially to
the multilayer in the direction perpendicular to the microwave magnetic field
induced by the stripline of the BFMR setup. The frequency of the
electromagnetic mode is independent of the static magnetic field. Consequently,
the predicted photon-magnon coupling is sensitive to the applied magnetic field
and thus can be used in magnetically tuneable metamaterials based on
simultaneously negative permittivity and permeability achievable thanks to the
YIG layer. We also suggest that the predicted photon-magnon coupling may find
applications in microwave quantum information systems
Higher spin supermultiplets in three dimensions: (2,0) AdS supersymmetry
Within the framework of (2,0) anti-de Sitter (AdS) supersymmetry in three
dimensions, we propose a multiplet of higher-spin currents. Making use of this
supercurrent, we construct two off-shell gauge formulations for a massless
multiplet of half-integer superspin , for every integer . In
the case, one formulation describes the linearised action for (2,0)
anti-de Sitter supergravity, while the other gives the type III minimal
supergravity action in (2,0) AdS superspace, with both linearised supergravity
actions originally derived in arXiv:1109.0496. The constructed massless actions
are then used to formulate topologically massive higher-spin supermultiplets in
(2,0) AdS superspace. Our results admit a natural extension to the case of
.Comment: 20 pages; V2: typos corrected, references and comments added, new
models described; V3: typos in eqs. (4.8) and (4.12) corrected. arXiv admin
note: text overlap with arXiv:1807.0909
Two-form supergravity, superstring couplings, and Goldstino superfields in three dimensions
We develop off-shell formulations for and anti-de
Sitter supergravity theories in three spacetime dimensions that contain gauge
two-forms in the auxiliary field sector. These formulations are shown to allow
consistent couplings of supergravity to the Green-Schwarz superstring with
or spacetime supersymmetry. In addition to being
-symmetric, the Green-Schwarz superstring actions constructed are also
invariant under super-Weyl transformations of the target space. We also present
a detailed study of models for spontaneously broken local supersymmetry in
three dimensions obtained by coupling the known off-shell and
supergravity theories to nilpotent Goldstino superfields.Comment: 63 pages; V2: minor correction