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Orbital Angular Momentum Transformation Of Optical Vortex With Aluminum Metasurfaces, Yuchao Zhang, Xiaodong Yang, Jie Gao Aug 2019

Orbital Angular Momentum Transformation Of Optical Vortex With Aluminum Metasurfaces, Yuchao Zhang, Xiaodong Yang, Jie Gao

Jie Gao

The orbital angular momentum (OAM) transformation of optical vortex is realized upon using aluminum metasurfaces with phase distributions derived from the caustic theory. The generated OAM transformation beam has the well-defined Bessel-like patterns with multiple designed topological charges from -1 to +2.5 including both the integer-order and fractional-order optical vortices along the propagation. The detailed OAM transformation process is observed in terms of the variations of both beam intensity and phase profiles. The dynamic distributions of OAM mode density in the transformation are further analyzed to illustrate the conservation of the total OAM. The demonstration of transforming OAM states ...


Second-Harmonic Optical Vortex Conversion From Ws₂ Monolayer, Arindam Dasgupta, Jie Gao, Xiaodong Yang Aug 2019

Second-Harmonic Optical Vortex Conversion From Ws₂ Monolayer, Arindam Dasgupta, Jie Gao, Xiaodong Yang

Jie Gao

Wavelength, polarization and orbital angular momentum of light are important degrees of freedom for processing and encoding information in optical communication. Over the years, the generation and conversion of orbital angular momentum in nonlinear optical media has found many novel applications in the context of optical communication and quantum information processing. With that hindsight, here orbital angular momentum conversion of optical vortices through second-harmonic generation from only one atomically thin WS2 monolayer is demonstrated at room temperature. Moreover, it is shown that the valley-contrasting physics associated with the nonlinear optical selection rule in WS2 monolayer precisely determines the output circular ...


Spatial Variation Of Vector Vortex Beams With Plasmonic Metasurfaces, Yuchao Zhang, Jie Gao, Xiaodong Yang Aug 2019

Spatial Variation Of Vector Vortex Beams With Plasmonic Metasurfaces, Yuchao Zhang, Jie Gao, Xiaodong Yang

Jie Gao

The spatial variation of vector vortex beams with arbitrary polarization states and orbital angular momentum (OAM) values along the beam propagation is demonstrated by using plasmonic metasurfaces with the initial geometric phase profiles determined from the caustic theory. The vector vortex beam is produced by the superposition of deflected right- and left-handed circularly polarized component vortices with different helical phase charges, which are simultaneously generated off-axially by the single metasurface. Besides, the detailed evolution processes of intensity profile, polarization distribution and OAM value along the beam propagation distance is analyzed. The demonstrated arbitrary space-variant vector vortex beam will pave the ...


Spontaneous Emission Rate Enhancement With Aperiodic Thue-Morse Multilayer, Ling Li, Cherian J. Mathai, Shubhra Gangopadhyay, Xiaodong Yang, Jie Gao Aug 2019

Spontaneous Emission Rate Enhancement With Aperiodic Thue-Morse Multilayer, Ling Li, Cherian J. Mathai, Shubhra Gangopadhyay, Xiaodong Yang, Jie Gao

Jie Gao

The emergence of multilayer metamaterials in the research field of enhancing spontaneous emission rates has recently received extensive attention. Previous research efforts mostly focus on periodic metal-dielectric multilayers in hyperbolic dispersion region; however, the influence of lattice order in subwavelength multilayers on spontaneous emission is rarely studied. Here, we observe the stronger Purcell enhancement of quantum dots coupled to the aperiodic metal-dielectric multilayer with Thue-Morse lattice order from elliptical to hyperbolic dispersion regions, compared to the periodic multilayer with the same metal filling ratio. This work demonstrates the potential of utilizing quasiperiodic metamaterial nanostructures to engineer the local density of ...


Manipulating Transverse Photovoltage Across Plasmonic Triangle Holes Of Symmetry Breaking, Marjan Akbari, Jie Gao, Xiaodong Yang Aug 2019

Manipulating Transverse Photovoltage Across Plasmonic Triangle Holes Of Symmetry Breaking, Marjan Akbari, Jie Gao, Xiaodong Yang

Jie Gao

The transverse photo-induced voltages generated by the photon drag effect under normally and obliquely incident circularly polarized light across the plasmonic symmetry-breaking isosceles-triangle holes and right-triangle holes have been characterized. It is observed that the sign of transverse photovoltage flips when the incident circular polarization is switched for both types of plasmonic triangle holes. However, the unbalanced photovoltage between two circular polarizations is achieved across the plasmonic right-triangle holes, compared to the balanced photovoltage in the plasmonic isosceles-triangle holes. Such manipulation of the sign and the amplitude of transverse photovoltage is enabled by the broken symmetries of the electric and ...


Generation Of Nondiffracting Vector Beams With Ring-Shaped Plasmonic Metasurfaces, Yuchao Zhang, Xiaodong Yang, Jie Gao Aug 2019

Generation Of Nondiffracting Vector Beams With Ring-Shaped Plasmonic Metasurfaces, Yuchao Zhang, Xiaodong Yang, Jie Gao

Jie Gao

Nondiffracting Bessel, Mathieu, and Weber vector beams are generated by using ring-shaped plasmonic geometric metasurfaces. The nondiffracting vector beam is produced by the superposition of two off-axis right-handed and left-handed circularly polarized nondiffracting scalar beams described by the Whittaker integral, which are simultaneously generated by a single metasurface with the ring-shaped phase profile. The polarization states of the generated nondiffracting vector beams are analyzed by the Stokes parameters and the orbital angular momentum states are measured by the beam interference. In addition, the selfhealing properties of nondiffracting vector beams are further demonstrated, showing that not only the beam profiles but ...


Enhanced Quantum Dots Spontaneous Emission With Metamaterial Perfect Absorbers, Wei Wang, Xiaodong Yang, Ting S. Luk, Jie Gao Aug 2019

Enhanced Quantum Dots Spontaneous Emission With Metamaterial Perfect Absorbers, Wei Wang, Xiaodong Yang, Ting S. Luk, Jie Gao

Jie Gao

Metamaterial perfect absorbers (PAs) made of a hexagonal array of holes on Ag-SiO 2 -Ag thin films have been realized and utilized to enhance the spontaneous emission rate and photoluminescence intensity of CdSe/ZnS quantum dots (QDs) spin-coated on the absorber top surface. Perfect absorption of incoming light occurs at the wavelength where the impedance is matched to that of the free space. When QDs strongly excite both the electric and magnetic resonances at this perfect absorption wavelength, a significant Purcell effect on the spontaneous emission process and enhanced radiative outcoupling of photoluminescence intensity are expected. For perfect absorbers with ...


Optical Transportation And Accumulation Of Microparticles By Self-Accelerating Cusp Beams, Weiwei Liu, Xiaodong Yang, Jie Gao Aug 2019

Optical Transportation And Accumulation Of Microparticles By Self-Accelerating Cusp Beams, Weiwei Liu, Xiaodong Yang, Jie Gao

Jie Gao

Most of the self-accelerating beams have monotonous single-channel bending structures, which greatly limit their applications in many fields such as microscopic imaging and particle manipulation. In this paper, the self-accelerating cusp beams with variable numbers of multichannel bending structures are generated to demonstrate the optical transportation and accumulation of micrometer polystyrene particles. The transportation velocity and optical force profiles of the microparticles moving along the bending channels of cusp beams are analyzed. Parallel particle transportation and particle accumulation manipulation from all the bending channels are further demonstrated. These results will inspire a lot of promising applications for self-accelerating beams especially ...


3d Janus Plasmonic Helical Nanoapertures For Polarization-Encrypted Data Storage, Yang Chen, Xiaodong Yang, Jie Gao Aug 2019

3d Janus Plasmonic Helical Nanoapertures For Polarization-Encrypted Data Storage, Yang Chen, Xiaodong Yang, Jie Gao

Jie Gao

Helical structures have attracted considerable attention due to their inherent optical chirality. Here, we report a unique type of 3D Janus plasmonic helical nanoaperture with direction-controlled polarization sensitivity, which is simply fabricated via the one-step grayscale focused ion beam milling method. Circular dichroism in transmission of as large as 0.72 is experimentally realized in the forward direction due to the spin-dependent mode coupling process inside the helical nanoaperture. However, in the backward direction, the nanoaperture acquires giant linear dichroism in transmission of up to 0.87. By encoding the Janus metasurface with the two nanoaperture enantiomers having specified rotation ...


Twisting Phase And Intensity Of Light With Plasmonic Metasurfaces, Yuchao Zhang, Xiaodong Yang, Jie Gao Jan 2019

Twisting Phase And Intensity Of Light With Plasmonic Metasurfaces, Yuchao Zhang, Xiaodong Yang, Jie Gao

Jie Gao

Twisting light in both phase and intensity has recently drawn great interests in various fields related to light-matter interactions such as optical manipulation of particles and quantum entanglement of photons. Conventionally, bulky optical components are required to produce such twisted optical beams, which significantly limits their applications in integrated photonics and optical chips. Here, we design and demonstrate aluminum plasmonic metasurfaces consisting of nanoslit antennas as ultracompact beam converters to generate the focused twisted beams in both phase and intensity across the visible wavelength range. The metasurface is encoded with the combined phase profile containing the helico-conical phase function together ...


Ultrasensitive Detection And Characterization Of Molecules With Infrared Plasmonic Metamaterials, F. Cheng, Xiaodong Yang, Jie Gao Jan 2019

Ultrasensitive Detection And Characterization Of Molecules With Infrared Plasmonic Metamaterials, F. Cheng, Xiaodong Yang, Jie Gao

Jie Gao

No abstract provided.


Structural Color Printing Based On Plasmonic Metasurfaces Of Perfect Light Absorption, F. Cheng, Jie Gao, T. S. Luk, Xiaodong Yang Jan 2019

Structural Color Printing Based On Plasmonic Metasurfaces Of Perfect Light Absorption, F. Cheng, Jie Gao, T. S. Luk, Xiaodong Yang

Jie Gao

No abstract provided.


Spiraling Light With Magnetic Metamaterial Quarter-Wave Turbines, J. Zeng, T. S. Luk, Jie Gao, Xiaodong Yang Jan 2019

Spiraling Light With Magnetic Metamaterial Quarter-Wave Turbines, J. Zeng, T. S. Luk, Jie Gao, Xiaodong Yang

Jie Gao

No abstract provided.


Strong Coupling Between Mid-Infrared Localized Plasmons And Phonons, W. Wan, Xiaodong Yang, Jie Gao Jan 2019

Strong Coupling Between Mid-Infrared Localized Plasmons And Phonons, W. Wan, Xiaodong Yang, Jie Gao

Jie Gao

No abstract provided.


Spin-Controlled Wavefront Shaping With Plasmonic Chiral Geometric Metasurfaces, Yang Chen, Xiaodong Yang, Jie Gao Jan 2019

Spin-Controlled Wavefront Shaping With Plasmonic Chiral Geometric Metasurfaces, Yang Chen, Xiaodong Yang, Jie Gao

Jie Gao

Metasurfaces, as a two-dimensional (2D) version of metamaterials, have drawn considerable attention for their revolutionary capability in manipulating the amplitude, phase, and polarization of light. As one of the most important types of metasurfaces, geometric metasurfaces provide a versatile platform for controlling optical phase distributions due to the geometric nature of the generated phase profile. However, it remains a great challenge to design geometric metasurfaces for realizing spin-switchable functionalities because the generated phase profile with the converted spin is reversed once the handedness of the incident beam is switched. Here, we propose and experimentally demonstrate chiral geometric metasurfaces based on ...


Realizing Structural Color Generation With Aluminum Plasmonic V-Groove Metasurfaces, W. Wang, D. Rosenmann, D. Czaplewski, Xiaodong Yang, Jie Gao Jan 2019

Realizing Structural Color Generation With Aluminum Plasmonic V-Groove Metasurfaces, W. Wang, D. Rosenmann, D. Czaplewski, Xiaodong Yang, Jie Gao

Jie Gao

No abstract provided.


Near-Infrared Chiral Plasmonic Metasurface Absorbers, Leixin Ouyang, Wei Wang, Daniel Rosenmann, David A. Czaplewski, Jie Gao, Xiaodong Yang Jan 2019

Near-Infrared Chiral Plasmonic Metasurface Absorbers, Leixin Ouyang, Wei Wang, Daniel Rosenmann, David A. Czaplewski, Jie Gao, Xiaodong Yang

Jie Gao

Chirality plays an essential role in the fields of biology, medicine and physics. However, natural materials exhibit very weak chiroptical response. In this paper, near-infrared chiral plasmonic metasurface absorbers are demonstrated to selectively absorb either the left-handed or right-handed circularly polarized light for achieving large circular dichroism (CD) across the wavelength range from 1.3 µm to 1.8 µm. It is shown that the maximum chiral absorption can reach to 0.87 and that the maximum CD in absorption is around 0.70. The current chiral metasurface design is able to achieve strong chiroptical response, which also leads to ...


Optical Nonlocality Induced Zitterbewegung Near The Dirac Point In Metal-Dielectric Multilayer Metamaterials, L. Sun, Jie Gao, Xiaodong Yang Jan 2019

Optical Nonlocality Induced Zitterbewegung Near The Dirac Point In Metal-Dielectric Multilayer Metamaterials, L. Sun, Jie Gao, Xiaodong Yang

Jie Gao

No abstract provided.


Klein Tunneling Near The Dirac Points In Metal-Dielectric Multilayer Metamaterials, L. Sun, Jie Gao, Xiaodong Yang Jan 2019

Klein Tunneling Near The Dirac Points In Metal-Dielectric Multilayer Metamaterials, L. Sun, Jie Gao, Xiaodong Yang

Jie Gao

No abstract provided.


Experimental Characterization Of Optical Nonlocalities In Metal-Dielectric Multilayer Metamaterials, L. Sun, F. Cheng, C. J. Mathai, S. Gangopadhyay, Jie Gao, Xiaodong Yang Jan 2019

Experimental Characterization Of Optical Nonlocalities In Metal-Dielectric Multilayer Metamaterials, L. Sun, F. Cheng, C. J. Mathai, S. Gangopadhyay, Jie Gao, Xiaodong Yang

Jie Gao

No abstract provided.


Generation Of Three-Dimensional Optical Cusp Beams With Ultrathin Metasurfaces, Weiwei Liu, Yuchao Zhang, Jie Gao, Xiaodong Yang Jan 2019

Generation Of Three-Dimensional Optical Cusp Beams With Ultrathin Metasurfaces, Weiwei Liu, Yuchao Zhang, Jie Gao, Xiaodong Yang

Jie Gao

Cusp beams are one type of complex structured beams with unique multiple self-accelerating channels and needle-like field structures owning great potentials to advance applications such as particle micromanipulation and super-resolution imaging. The traditional method to generate optical catastrophe is based on cumbrous reflective diffraction optical elements, which makes optical system complicated and hinders the nanophotonics integration. Here we design geometric phase based ultrathin plasmonic metasurfaces made of nanoslit antennas to produce three-dimensional (3D) optical cusp beams with variable numbers of self-accelerating channels in a broadband wavelength range. The entire beam propagation profiles of the cusp beams generated from the metasurfaces ...


Enhanced Structural Color Generation In Aluminum Metamaterials Coated With A Thin Polymer Layer, F. Cheng, Xiaodong Yang, D. Rosenmann, L. Stan, D. Czaplewski, Jie Gao Jan 2019

Enhanced Structural Color Generation In Aluminum Metamaterials Coated With A Thin Polymer Layer, F. Cheng, Xiaodong Yang, D. Rosenmann, L. Stan, D. Czaplewski, Jie Gao

Jie Gao

No abstract provided.


Broadband Polarization Conversion With Anisotropic Plasmonic Metasurfaces, W. Cao, Xiaodong Yang, Jie Gao Jan 2019

Broadband Polarization Conversion With Anisotropic Plasmonic Metasurfaces, W. Cao, Xiaodong Yang, Jie Gao

Jie Gao

No abstract provided.


All-Metal Structural Color Printing Based On Aluminum Plasmonic Metasurfaces, Z. Li, W. Wang, D. Rosenmann, D. Czaplewski, Xiaodong Yang, Jie Gao Jan 2019

All-Metal Structural Color Printing Based On Aluminum Plasmonic Metasurfaces, Z. Li, W. Wang, D. Rosenmann, D. Czaplewski, Xiaodong Yang, Jie Gao

Jie Gao

No abstract provided.


Broadband Infrared Absorbers With Stacked Double Chromium Ring Resonators, H. Deng, L. Stan, D. Czaplewski, Jie Gao, Xiaodong Yang Jan 2019

Broadband Infrared Absorbers With Stacked Double Chromium Ring Resonators, H. Deng, L. Stan, D. Czaplewski, Jie Gao, Xiaodong Yang

Jie Gao

No abstract provided.


Aluminum Plasmonic Metamaterials For Structural Color Printing, F. Cheng, Jie Gao, L. Stan, D. Rosenmann, D. Czaplewski, Xiaodong Yang Jan 2019

Aluminum Plasmonic Metamaterials For Structural Color Printing, F. Cheng, Jie Gao, L. Stan, D. Rosenmann, D. Czaplewski, Xiaodong Yang

Jie Gao

No abstract provided.