Selectively steering photon spin angular momentum via electron-induced optical spin Hall effect

The development of the optical spin Hall effect (OSHE) realizes the splitting of different spin components, contributing to the manipulation of photon spin angular momentum that acts as the information carrier for quantum technology. However, OSHE with optical excitation lacks active control of photon angular momentum at deep subwavelength scale because of the optical diffraction limit. Here, we experimentally demonstrate a selective manipulation of photon spin angular momentum at a deep subwavelength scale via electron-induced OSHE in Au nanoantennas. The inversion of the OSHE radiation pattern is observed by angle-resolved cathodoluminescence polarimetry with the electron impact position shifting within 80 nm in a single antenna unit. By this selective steering of photon spin, we propose an information encoding with robustness, privacy, and high level of integration at a deep subwavelength scale for the future quantum applications.

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The spin Hall effect of light in moving medium

Modern Physics Letters B ◽

10.1142/s0217984916504273 ◽

2017 ◽

Vol 31 (01) ◽

pp. 1650427 ◽

Cited By ~ 1

Author(s):

Hehe Li ◽

Xinzhong Li ◽

Jingge Wang

Keyword(s):

Angular Momentum ◽

Gravitational Field ◽

Hall Effect ◽

Inhomogeneous Medium ◽

Maxwell's Equations ◽

Potential Method ◽

Spin Hall Effect ◽

Moving Medium ◽

Spin Angular Momentum ◽

Effect Of Light

In this paper, we investigate the spin Hall effect of light in moving inhomogeneous medium using the Gordon metric and the Maxwell’s equations in the gravitational field. Light experiences a moving medium as a gravitational field by means of the Gordon metric. It is shown that the spin Hall effect of light is modified by the motion of medium, and the deflection of the ray trajectory is dependent on the polarization and the motion of the medium. It is interesting that there is no coupling of the spin angular momentum of light and the effective gravitational field when the medium is moving along the direction of the gradient [Formula: see text]. The results provide a potential method for controlling the spin Hall effect of light in medium.

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Spin Hall effect of light in inhomogeneous nonlinear medium

Modern Physics Letters B ◽

10.1142/s021798491550270x ◽

2016 ◽

Vol 30 (02) ◽

pp. 1550270

Author(s):

Hehe Li ◽

Xinzhong Li

Keyword(s):

Angular Momentum ◽

Hall Effect ◽

Orbital Angular Momentum ◽

Nonlinear Medium ◽

Spin Hall Effect ◽

Phase Front ◽

Spin Angular Momentum ◽

Linear Complex ◽

Complex Valued ◽

Effect Of Light

In this paper, we investigate the spin Hall effect of a polarized Gaussian beam (GB) in a smoothly inhomogeneous isotropic and nonlinear medium using the method of the eikonal-based complex geometrical optics which describes the phase front and cross-section of a light beam using the quadratic expansion of a complex-valued eikonal. The linear complex-valued eikonal terms are introduced to describe the polarization-dependent transverse shifts of the beam in inhomogeneous nonlinear medium which is called the spin Hall effect of beam. We know that the spin Hall effect of beam is affected by the nonlinearity of medium and include two parts, one originates from the coupling between the spin angular momentum and the extrinsic orbital angular momentum due to the curve trajectory of the center of gravity of the polarized GB and the other from the coupling between the spin angular momentum and the intrinsic orbital angular momentum due to the rotation of the beam with respect to the central ray.

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Optical Spin Hall Effect in Closed Elliptical Plasmonic Nanoslit with Noncircular Symmetry

Nanomaterials ◽

10.3390/nano11040851 ◽

2021 ◽

Vol 11 (4) ◽

pp. 851

Author(s):

Xiaorong Ren ◽

Xiangyu Zeng ◽

Chunxiang Liu ◽

Chuanfu Cheng ◽

Ruirui Zhang ◽

...

Keyword(s):

Angular Momentum ◽

Hall Effect ◽

Light Field ◽

Analytical Calculation ◽

Spin Hall Effect ◽

Spin Component ◽

Phase Gradient ◽

Bright Spots ◽

Principal Axes ◽

Output Field

We investigated the optical spin Hall effect (OSHE) of the light field from a closed elliptical metallic curvilinear nanoslit instead of the usual truncated curvilinear nanoslit. By making use of the characteristic bright spots in the light field formed by the noncircular symmetry of the elliptical slit and by introducing a method to separate the incident spin component (ISC) and converted spin component (CSC) of the output field, the OSHE manifested in the spot shifts in the CSC was more clearly observable and easily measurable. The slope of the elliptical slit, which was inverse along the principal axes, provided a geometric phase gradient to yield the opposite shifts of the characteristic spots in centrosymmetry, with a double shift achieved between the spots. Regarding the mechanism of this phenomenon, the flip of the spin angular momentum (SAM) of CSC gave rise to an extrinsic orbital angular momentum corresponding to the shifts of the wavelet profiles of slit elements in the same rotational direction to satisfy the conservation law. The analytical calculation and simulation of finite-difference time domain were performed for both the slit element and the whole slit ellipse, and the evolutions of the spot shifts as well as the underlying OSHE with the parameters of the ellipse were achieved. Experimental demonstrations were conducted and had consistent results. This study could be of great significance for subjects related to the applications of the OSHE.

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Conservation of Angular Momentum, Transverse Shift, and Spin Hall Effect in Reflection and Refraction of an Electromagnetic Wave Packet

Physical Review Letters ◽

10.1103/physrevlett.96.073903 ◽

2006 ◽

Vol 96 (7) ◽

Cited By ~ 340

Author(s):

Konstantin Yu. Bliokh ◽

Yury P. Bliokh

Keyword(s):

Angular Momentum ◽

Electromagnetic Wave ◽

Wave Packet ◽

Hall Effect ◽

Spin Hall Effect ◽

Reflection And Refraction ◽

Momentum Transverse

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Spin-to-orbital angular momentum conversion in spin Hall effect of light

Optics Communications ◽

10.1016/j.optcom.2011.10.014 ◽

2012 ◽

Vol 285 (6) ◽

pp. 864-871 ◽

Cited By ~ 7

Author(s):

Hailu Luo ◽

Shuangchun Wen ◽

Weixing Shu ◽

Dianyuan Fan

Keyword(s):

Angular Momentum ◽

Hall Effect ◽

Orbital Angular Momentum ◽

Spin Hall Effect ◽

Effect Of Light

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Orbital torque in magnetic bilayers

10.21203/rs.3.rs-509141/v1 ◽

2021 ◽

Author(s):

Dongjoon Lee ◽

Dongwook Go ◽

Hyeon-Jong Park ◽

Wonmin Jeong ◽

Hye-Won Ko ◽

...

Keyword(s):

Angular Momentum ◽

Electric Field ◽

Hall Effect ◽

Spin Hall Effect ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Spin Currents ◽

Fundamental Process ◽

Metal Bilayers

Abstract The spin Hall effect describes an electric-field-induced generation of spin currents through spin-orbit coupling. Since the spin-orbit coupling alone cannot generate the angular momentum, there must be a more fundamental process of the spin Hall effect. Theories suggested that an electric-field-induced generation of orbital currents, called orbital Hall effect, is the fundamental process, and spin currents are subsequently converted from orbital currents. Despite its fundamental importance, the orbital Hall effect has not been confirmed experimentally. Motivated by a recent theoretical proposal of torque generation by orbital angular momentum injection, we examine the current-induced torque experimentally in various ferromagnet/heavy metal bilayers. We find that the net torque in Ni/Ta bilayers is opposite in sign to the spin Hall theory prediction but instead consistent with the orbital Hall theory, which confirms the orbital torque generated by the orbital Hall effect. It will invigorate researches on spin-orbit-coupled phenomena based on orbital engineering.

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Steering Asymmetric Spin Splitting in Photonic Spin Hall Effect by Orbital Angular Momentum

Acta Optica Sinica ◽

10.3788/aos201333.1126002 ◽

2013 ◽

Vol 33 (11) ◽

pp. 1126002 ◽

Cited By ~ 2

Author(s):

张进 Zhang Jin ◽

罗朝明 Luo Zhaoming ◽

罗海陆 Luo Hailu ◽

文双春 Wen Shuangchun

Keyword(s):

Angular Momentum ◽

Hall Effect ◽

Orbital Angular Momentum ◽

Spin Hall Effect ◽

Spin Splitting

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Transverse Angular Momentum and Geometric Spin Hall Effect of Light

Physical Review Letters ◽

10.1103/physrevlett.103.100401 ◽

2009 ◽

Vol 103 (10) ◽

Cited By ~ 142

Author(s):

Andrea Aiello ◽

Norbert Lindlein ◽

Christoph Marquardt ◽

Gerd Leuchs

Keyword(s):

Angular Momentum ◽

Hall Effect ◽

Spin Hall Effect ◽

Effect Of Light

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Titanium dioxide metasurface manipulating high-efficiency and broadband photonic spin Hall effect in visible regime

Nanophotonics ◽

10.1515/nanoph-2020-0290 ◽

2020 ◽

Vol 9 (14) ◽

pp. 4327-4335

Author(s):

Wei Zhu ◽

Ruisheng Yang ◽

Guangzhou Geng ◽

Yuancheng Fan ◽

Xuyue Guo ◽

...

Keyword(s):

Titanium Dioxide ◽

Angular Momentum ◽

Hall Effect ◽

High Efficiency ◽

Berry Phase ◽

Spin Hall Effect ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

High Efficient

AbstractThe interactions of photonic spin angular momentum and orbital angular momentum, i.e., the spin-orbit coupling in focused beams, evanescent waves or artificial photonic structures, have attracted intensive investigations for the unusual fundamental phenomena in physics and potential applications in optical and quantum systems. It is of fundamental importance to enhance performance of spin-orbit coupling in optics. Here, we demonstrate a titanium dioxide (TiO2)–based all-dielectric metasurface exhibiting a high efficient control of photonic spin Hall effect (PSHE) in a transmissive configuration. This metasurface can achieve high-efficiency symmetric spin-dependent trajectory propagation due to the spin-dependent Pancharatnam-Berry phase. The as-formed metadevices with high-aspect-ratio TiO2 nanofins are able to realize (86%, measured at 514 nm) and broadband PSHEs in visible regime. Our results provide useful insights on high-efficiency metasurfaces with versatile functionalities in visible regime.

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