Photonic Spin Hall Effect Research Articles

Tunable photonic spin Hall effect in a tripod atom-light configuration

Tunable photonic spin Hall effect in a tripod atom-light configuration

Photonic spin Hall effect behavior of vortex beam in surface plasmon resonance

Photonic spin Hall effect behavior of vortex beam in surface plasmon resonance

Effectively suppressed reflected photonic spin Hall effect.

The photonic spin Hall effect can engender transverse spatial and angular displacements in both transmission and reflection, with significant applications in optical imaging, edge detection, and the development of spin-based nanophotonic devices. While previous research has focused on enhancing the photonic spin Hall effect, suppression can be beneficial for photonic spin-switching, offering advantages such as increased speed and sensitivity in nanophotonic devices. In this study, we establish a quantitative correlation between the reflection coefficient and the transverse spatial and angular displacements of reflected light, as induced by the photonic spin Hall effect, grounded in electromagnetic theory. We find that the transverse spatial displacement of reflected light can be eliminated under the condition r pp = -r ss , where r denotes the reflection coefficient, and the first (second) superscript denotes the polarization of the reflected (incident) light. This condition applies to light with arbitrary polarization states, at arbitrary incident angles, and is independent of wavelength and beam waist. A similar outcome is obtained for the transverse angular displacement of the reflected light. Such distinctive displacements are attainable through the use of an electromagnetic interface that satisfies the reflected condition r pp = -r ss . Additionally, we provide a succinct overview of the methodologies for constructing reflective spin switches.

Enhanced photonic spin Hall effect of the high order Hermite-Gauss mode on a generic conducting sheet.

The Hermite-Gauss mode (HGM) has received great attention due to its interesting properties and extensive applications. In this Letter, we propose a comprehensive theory of the enhanced photonic spin Hall effect (PSHE) for high order HGM under p- or s-polarization near Brewster's angle (BA) on a generic conducting sheet. This BA rises from the destructive interference induced by the surface current on such sheet. The transverse PSHE shift can be tailored by altering the order of HGM and sheet conductivity. Besides, we design a PSHE enabled flexible polarization sensor with tunable sensitivity. It can detect the real or imaginary part of the sheet conductivity with a sensitivity of over 105λ/S. This work provides useful insight and promising application of the PSHE for high order HGM.

Photonic Spin Hall Effect by Electro-optically Induced Pancharatnam-Berry Phases

Photonic Spin Hall Effect by Electro-optically Induced Pancharatnam-Berry Phases

Tunable photonic spin Hall effect in the Weyl semimetals

Time-reversal symmetry-breaking Weyl semimetals (WSMs) exhibit an interesting optical response in the mid-infrared band, offering what we believe to be a novel approach to study the manipulation of the photonic spin Hall effect (PSHE). This article theoretically investigates the PSHE phenomenon in a prism-coupled structure composed of the WSMs. It is found that the excitation of surface plasmon polaritons (SPPs) and the nonreciprocity inherent in WSMs have a positive effect on enhancing the PSHE phenomenon of the reflected light. Especially, the PSHE can also be manipulated by varying the separation distance and twist angle between the Weyl nodes. Through parameter optimization, we obtained a lateral displacement of 12.14 μm. The effects of the separation distance between Weyl nodes, the twist angle, and the incident light angle on the PSHE were further elucidated. We believe the tunable PSHE with WSMs can provide promising avenues for developing spintronic devices, as well as other photonic applications.

Nonreciprocal cavity magnonics system for amplification of photonic spin Hall effect

Nonreciprocal cavity magnonics system for amplification of photonic spin Hall effect

Enhanced photonic spin Hall shift and scattering efficiency through chiral nanoparticles

The photonic spin Hall effect, arising from the spin-orbit interaction of light, has attracted rapt scientific interest owing to its applicability. Due to the limited strength of the spin-orbit interaction, the resulting photonic spin Hall shift (PSHS) is very small. In addition, the low scattering intensity hinders the applicability of the PSHS in higher-dimensional systems. Here, we explore the effect of the chirality of the particle on the far-field PSHS and the scattered intensity. We demonstrate that the chiral particle strongly supports quasi-dual symmetry when the handedness of the incident wave and the sphere match, in contrast to unmatched handedness. Under dual transformation, the spin-orbit interaction is amplified, resulting in enhanced PSHS with a characteristic redshift. Meanwhile, the far-field scattering intensity is optimized without changing the geometry of the particle. The strong spin-orbit interaction in the near-field arises due to the optical singularities in the far-vicinity, which leads to a large effective transverse force. Our results not only provide a route to tune the PSHS and scattering efficiency but might have the potential to characterize the degree of handedness of the nanoparticle.

Photonic spin Hall effect at an optical bound state in the continuum

Photonic spin Hall effect at an optical bound state in the continuum

Theoretical design of manipulating the number of photonic spin Hall effect channels with Tamm plasmon polariton and its sensing capabilities

In this paper, the induction effect of Tamm plasmon polariton (TPP) mode on photonic spin Hall effect (PSHE) is discovered. As the incident angle increases, the TPP mode exhibits a polarization separation effect, which is conducive to the emergence of PSHE. PSHE is excited near the absorption frequencies of both the TM and TE waves, with H displacement dominating the TM wave and V displacement dominating the TE wave. The number of TPP channels is usually half that of PSHE, which enables quantitative control over the number of PSHE. In addition, the obtained PSHE has more potential as a sensor. On the one hand, compared with the TPP absorption peak, the PSHE peak is narrower, making a ten-fold increase in resolution. Different channels of PSHE can be used to detect different refractive index (RI) ranges, thus expanding the linear range. Moreover, analyzing PSHE displacement helps capture subtle RI changes, which is beneficial to the detection of gases, while the TPP peak fails to possess this ability.

Direct observation of the enhanced photonic spin Hall effect in a subwavelength grating.

The photonic spin Hall effect (PSHE) in surface plasmon resonance (SPR) structures has great potential for various polarization-sensitive applications and devices. Here, using optical weak measurement, we observe spin-dependent and spin-independent angular shifts of the reflected beam, enhanced by SPR in a subwavelength nickel grating. An enhanced in-plane photonic spin Hall effect manifested in the angular splitting of circularly polarized photons with opposite helicity signs is demonstrated. We theoretically and experimentally demonstrate that angular in-plane shifts can be changed from spin-independent (Goos-Hänchen (GH) shift) to spin-dependent (PSHE) when the incident beam polarization state changes. The SPR-induced depolarization of light and the mixing of polarization states are detected. High purity of spin separation and a high degree of circular polarization are achieved with an optimal polarization state (preselection angle) and a resonance angle of incidence. A novel, to the best of our knowledge, phenomenon of the spinless spatial separation of two orthogonal components of the field with diagonal linear polarizations is demonstrated.

Photonic Spin Hall Effect of Nanoparticles: Fundamentals, Advances, and Applications

AbstractThe net angular momentum of light remains conserved during propagation. This conservation leads to a spin transport which becomes evident when light encounters a refractive index gradient, i.e., when it is reflected, refracted, or scattered. The phenomenon is so‐called as the spin‐orbit interaction (SOI) of light has paved the way to manipulate the light‐matter interaction at the nanoscale and has remained the core of many recent studies. Particularly, the photonic spin Hall effect (PSHE) which is the microscopic spin splitting into circular polarization has given rise to novel applications, for example, precision metrology. The PSHE is well explored at planar interfaces, however much less attention is given to it when the optical potential gradient is of higher dimensionality, i.e., for nanoparticles. In this review, the theoretical description of the PSHE as well as the SOI in the scattering of light from nanoparticles are covered. Recent advances and trends in the PSHE in nanoparticles are reviewed. The review is concluded with suggestions for some novel directions in the field of PSHE of nanoparticles.

Reconfigurable Generation and Spin Manipulation of Structured Beams Based on Cascaded Liquid Crystal Pancharatnam–Berry Phase Elements

AbstractStructured light, with spatially varying amplitude, phase, and polarization, has attracted widespread attention for its potential application in many fields ranging from optical communications to imaging. However, it remains a challenge to realize reconfigurable manipulation of structured light beams in a compact and convenient method. Here, through mechanical operations on the two cascaded liquid crystal Pancharatnam–Berry phase elements such as rotation and translation, diverse kinds of typical structured light can be experimentally generated in a reconfigurable manner, including Gaussian, Hermitian–Gaussian, vortex, and cylindrical vector beams. Moreover, by rotating a liquid crystal element, tunable photonic spin Hall effect is also achieved in the proposed cascaded‐elements scheme, which allows for tailoring the spin‐dependent shifts in the structured beams. In such a reconfigurable generator, the mechanical operations on the phase element bring new degrees of freedom into the manipulation of structured light field, which may pave the avenue for future optical applications.

A multitasking renal function assessment janus biosensor based on photonic spin Hall effect at epsilon-near-zero threshold frequency of YaBa2Cu3O7 ceramic material

A multitasking renal function assessment janus biosensor based on photonic spin Hall effect at epsilon-near-zero threshold frequency of YaBa2Cu3O7 ceramic material

Highly sensitive photonic spin Hall effect sensor with graphene-coated surface exciton polariton structure

The photonic spin Hall effect (PSHE) in a graphene-coated surface exciton polariton (SEP) structure is investigated in this work. The transverse shift of 32.95λ0 (17.53 μm) is achieved with the optimum graphene-coated SEP structure in the gaseous environment under λ0 = 532 nm illumination, which provides a 2.46-fold improvement compared to the optimum conventional SEP structure. The transverse shift is further improved to 76.39λ0 (i.e., 40.64 μm) with the graphene-coated long-range SEP (LRSEP) in the aqueous environment. Refractive index sensors based on the enhanced PSHE are proposed for sensing applications in the gaseous and aqueous environment, respectively, which possess the bulk refractive index sensitivities of 24424.4λ0 (12993.78 µm) 1/RIU (RIU: refractive index unit) and 57336.6λ0 (30503.1 µm) 1/RIU. The combination of SEP (LRSEP) and graphene layers provides a promising approach for enhancing the transverse shift of PSHE, and may find potential applications in gas sensing, chemical sensing, and biosensing base on the enhanced PSHE.

Highly switchable photonic spin hall effect in vanadium dioxide grating structure

Highly switchable photonic spin hall effect in vanadium dioxide grating structure

Singular photon spin Hall effect in chiral-graphene heterostructures and its application in chirality detection.

In this paper, we consider the singular photonic spin Hall effect (PSHE) in a chiral-graphene-chiral (CGC) heterostructure in the THz band. We investigate the impact of a chiral medium on reflectance spectra and the modulation of the Fermi energy on the surface conductivity of graphene. Our study shows that placing a chiral medium on both sides of a monolayer of graphene results in an enhanced transverse shift (TS) compared to placing a non-chiral medium. Moreover, the direction of the TS of the PSHE can be altered by adjusting the sign of the chirality parameter and the Fermi energy of graphene. Finally, we establish a quantitative relationship between the PSHE and the chirality parameter and the Fermi energy of graphene. By dynamically modulating the PSHE in graphene, it is possible to flexibly detect chirality parameters. This work opens up new avenues for chiral molecular detection and graphene-PSHE dynamic modulation.

A method of multi-bit optical coding by constructing Brewster angles to enhance photonic spin Hall effect

The photonic spin Hall effect, characterized by its polarization-driven spin-related displacement, has played an essential role in coding information processing. In this Letter, using a two-period double-layer dielectric plate, the displacement changes within the angle region are first observed, and a two-bit effective coding is achieved through non-uniform quantization of displacement values and coding. Afterward, by constructing Brewster angles (BAs), effective three-bit coding is achieved at the selected BA by dividing the angle domain. By changing the relative refractive index of the constituent materials (nB), effective coding is achieved at corresponding angles (45°–85°). By connecting two-bit and three-bit coding, a five-bit coding is fulfilled. By setting the last six invalid values, effective correspondence of 26 English letters is obtained. At the same time, the largest displacement peak itself is huge and varies accordingly with different values of nB. This work can provide some reference for designing optical coders.

Ultrathin metal-dielectric planar interface for high-performance photonic spin Hall effect

Abstract This study explores the photonic spin Hall effect (PSHE) with a focus on its sensitivity to incident wave polarization and physical parameter variations. Traditionally surface plasmonic resonance (SPR) systems mainly enhance H-polarized PSHE. However, our proposed method involves an ultrathin metal layer, capped with a glass dielectric layer on a glass substrate, to achieve high-performance PSHE for both H- and V-polarization waves. This high-performance PSHE in terms of enhancement in PSHE magnitudes arises from the simultaneous presence of SPR and waveguiding effects, resulting in the emergence of hybrid TE and TM modes. Investigating Au and Ag ultrathin metal layers, we find that the highest H-polarized PSHE occurs at ~1.52 × 10^6 nm and ~2.05 × 10^5 nm for Au and Ag, respectively. Similarly, for Vpolarized incident light, maximum enhanced PSHE is observed at ~1.58 × 10^5 nm and ~9.48 × 10^4 nm for Au and Ag, respectively. By adjusting the thickness of the metal and/or glass cap layer, precise control over PSHE amplitude and active polarization response is achievable. This research unveils unique capabilities for generating hybrid modes that enhance PSHE for both polarizations, offering a potential platform for developing tunable polarizationfavorable spin optics optoelectronic devices.

Observation of the enhanced dual-split photonic spin Hall effect in wavelength domain via a helical fiber grating

To date, the photonic spin Hall effect (PSHE) has been studied and observed only in the space and momentum domains. Direct observation of the PSHE in the wavelength domain remains unexplored. In this work, we demonstrate both theoretically and experimentally the enhanced PSHE in the wavelength domain via a helical long-period fiber grating (HLPG), where the spin-dependent dual-split in the transmission spectrum of the utilized HLPG has been observed. This is unlike the PSHEs reported thus far, where a mono-splitting of the light is observed in either the space or the momentum domains. The proposed method provides an additional degree of freedom to observe the PSHE, which paves the way for exploiting all fiber-based HLPGs in chiral photonics, chiral sensors, and fine precise measurements.