28 research outputs found
Generation and high-resolution imaging of higher-order polarization via metasurface
The generation and focusing properties of higher-order polarized beams have attracted lots of interests due to its significant applications. In this paper,we derived the formula of transforming linear polarization into higher-order polarization, which is applicable to generating arbitrary order polarization. Based on the derived formula, the focusing properties of higher-order polarization by dielectric metasurface lens are studied , which exhibit an Abbe-limit-breaking feature for small numerical aperture, i.e., NA<0.6. When a binary phase (0 & {\pi}) is further imposed on the aperture of metasurface lens, the focusing spot of fourth-order polarization breaks Abbe limit even by 14.3% at NA= 0.6. In addition, the effect of fabrication tolerance, say, substrate thickness and central deviation, on the focusing feature of higher-order polarization is also investigated. Our study may find significant applications in achieving higher-resolution lithography and imaging, say, by just replacing conventional linear or circular polarization with higher-order polarization
Supplementary document for Two-level optical encryption platform via electrical-driven tri-channel metasurfaces integrated liquid cystal - 6514450.pdf
Two-level optical encryption platform via electrical-driven tri-channel metasurfaces integrated liquid crystal: supplemental documen
Physical essence of propagable fractional-strength optical vortices in free space
Fractional-order vector vortex beams are recently demonstrated to be new carriers of fractional-strength optical vortices. However, why can those new vortex beams formed by the combination of both unstable states propagate stably in free space? Here, we solve this scientific problem by revealing the physical essence of propagable fractional-strength optical vortices in free space.Three new understandings regarding those peculiar vortex beams are therefore proposed, namely Abbe diffraction limit, phase evolution of vortex beam, and phase binary time vector property.For the first one, owing to Abbe diffraction limit, the inherent polarization modes are intertwined together, thereby maintaining the entire peculiar vortex beams in free space. For the second one, we demonstrate the phase evolution of vortex beam, which is the physical reason of polarization rotation of fractional-order VVBs. For the third one, the phase is not merely a scalar attribute of light beam, but manifests a binary time vector property. This work provides entirely different physical viewpoints on the phase of vortex beam and Abbe diffraction limit, which may deepen our knowledge on the behavior of light beam in classical optics
Electrochemical Control over the Optical Properties of II–VI Colloidal Nanoplatelets by Tailoring the Station of Extra Charge Carriers
An
electrochemical (EC) method has been successfully applied to
regulate the optical properties of nanocrystals, such as reducing
their gain threshold by EC doping and enhancing their photoluminescence
intensity by EC filling of trap states. However, the processes of
EC doping and filling are rarely reported simultaneously in a single
study, hindering the understanding of their underlying interactions.
Here, we report the spectroelectrochemical (SEC) studies of quasi-two-dimensional
nanoplatelets (NPLs), intending to clarify the above issues. EC doping
is successfully achieved in CdSe/CdZnS core/shell NPLs, with red-shifted
photoluminescence and a reversal of the emission intensity trend.
The injection of extra electrons (holes) into the conduction (valence)
band edges needs high bias voltages, while the passivation/activation
process of trap states with the shift of Fermi level starts at lower
EC potentials. Then, we explore the role of excitation light conditions
in these processes, different from existing SEC research studies.
Interestingly, increasing the laser power density can hinder EC electron
injection, whereas decreasing the excitation energy evades the passivation
process of trap states. Moreover, we demonstrate that EC control strategies
can be used to realize color display and anti-counterfeiting applications
via simultaneously tailoring the photoluminescence intensity of red-
and green-emitting NPLs
Supplementary document for A polarization tunable transmitted full-color display with enhanced switchability - 6213452.pdf
Clean revised manuscrip
Supplementary document for A polarization tunable transmitted full-color display with enhanced switchability - 6188181.pdf
Clean revised manuscrip
Extraction of inherent polarization modes from a single light beam
Superposition of two independent orthogonally polarized beams is a conventional principle of creating a new light beam. Here, we intend to achieve the inverse process, namely, extracting inherent polarization modes from a single light beam. However, inherent polarization modes within a light beam are always entangled so that a stable polarization is maintained during propagation in free space. To overcome this limitation, we report an approach that breaks the modulation symmetry of a light beam, thereby disentangling the inherent polarization modes. Using polarization mode competition along with an optical pen, polarization modes are extracted at will in the focal region of an objective lens. This work demonstrates polarization mode extraction from a light beam, which will not only provide an entirely new principle of polarization modulation but also pave the way for multidimensional manipulation of light fields, thereby facilitating extensive developments in optics
Supplementary document for Thermal tuning nanoprinting based on liquid crystal tunable dual-layered metasurfaces for optical information encryption - 6798346.pdf
Supporting informatio
Free-space creation of ultralong anti-diffracting light beam with multiple energy oscillations adjusted using optical pen
A light beam propagating with an infinite anti-diffracting distance requires infinite power to preserve its shape. However, the fundamental barrier of finite power in free space has made the problem of diffraction insurmountable over the past few decades. Here, to overcome this limitation, we report an approach that employs the multiple energy oscillation mechanism, thereby permitting the creation of a light beam with an ultralong anti-diffracting distance in free space. The anti-diffracting distance is no longer restricted by finite power in free space but instead depends on the number of energy oscillations. This unprecedented propagation behavior is attributed to a new understanding of non-diffractive light beam: when an anti-diffracting light beam completely discharges its energy, it cannot recharge again. A versatile optical pen is therefore developed to manipulate the number, amplitude, position and phase of energy oscillations for an arbitrary numerical aperture of a focusing lens so that energy recharge can occur in free space and multiple energy oscillations can be realized. A light beam with a tunable number of energy oscillations is eventually generated in free space and propagates along a wavy trajectory. This work will enable extending non-diffractive light beams to an expanded realm and facilitate extensive developments in optics and other research fields, such as electronics and acoustics
Establishment of the fundamental phase-to-polarization link in classical optics
Vector polarization induced by a change in scalar phase has been far beyond our understanding of the relationship between polarization and phase in classical optics due to the entanglement of inherent polarized modes of light beams. To overcome this limitation, we establish this miraculous relationship by the principle of phase vectorization, which can transform three particular phases into linear, circular and elliptical polarizations. A polarized-spatial light modulator based on the principle of phase vectorization can be achieved using a phase-only spatial light modulator, which not only enables pixel-level polarization manipulation of light beams in a real-time dynamic way but also simultaneously retains complete phase control. This work demonstrates the phase-to-polarization link and reports the creation of polarized-spatial light modulator, which will transform our view of the natural properties of light beam and pave the way for the era of vector optics
