Guoyan Dong

• PhD
• University of Chinese Academy of Sciences

Mie resonances in dielectric particles play a crucial role in light–matter interaction, characterized by strong multipolar optical responses and low dissipative losses. This study presents an innovative methodology for precise discrimination of the size and quantity of deep-subwavelength microspheres by leveraging Fano resonances in coupled magneti...

Anderson localization has inspired tremendous effort in exploring underlying physics regarding electron, atom, and photon transport in disordered lattices. However, due to the difficulty in implementing periodic trapping potential for neutral excitons, observing Anderson localization of excitons in disordered semiconductors remains challenging. We...

Coupled Mie resonance via a symmetrical block-particle trimer is proposed to significantly enhance near-field interactions for sensing the ambient changes. Unlike the resonances of individual particles and dimers, both the frequency and strength of the enhanced magnetic and electric dipole resonances in the trimer exhibit excellent linear responses...

Quasi-two-dimensional (quasi-2D) Dion-Jacobson (DJ) perovskites are promising candidates for fabricating high-performance blue-emitting perovskite light-emitting diodes (PeLEDs) because of their strong quantum/dielectric confinement and high stability. However, obtaining high-efficiency blue PeLEDs based on DJ perovskites remains a major challenge....

Since quasicrystals provide additional freedom to expand photonic bandgap, dielectric quasiperiodic sequences of broadbands become crucial for implementing low-loss omnidirectional reflectors or filters. The current major challenge is to find an elegant scheme to construct angle-insensitive multilayer structures with fewer layer numbers. In this wo...

A three-dimensional compact prototype of a photonic crystal directive antenna is constructed for beam steering and directional radiation in the microwave. Experiments demonstrate that the array of dielectric cylinders placed in a U-shape open metal cavity can be profitably exploited to act as a high-efficiency splitting directive antenna in particu...

A multi-image encryption method based on singular value decomposition ghost imaging and RSA public-key cryptography (RSVDGI) is proposed. Radon transform (RT) is first carried out on the target images to obtain Radon spectrums, and then, QR encoding is performed on it. The QR-coded image is used as a plaintext image for singular value decomposition...

Since quasicrystals provide additional freedom to expand photonic bandgap, dielectric quasi-periodic sequences of broadbands become crucial for implementing low-loss omnidirectional reflectors or filters. The current major challenge is to find an elegant scheme to construct angle-insensitive multilayer structures with fewer layer numbers. In this w...

Quantum dot color conversion films (QD-CCFs) are proposed for use infull-color micron-sized light-emitting diode (micro-LED) displays, but quicklyand precisely evaluating their optical quality and identifying the bad pixelsamong them remain challenging. In this work, microscale fluorescencespectroscopy (MFS) is demonstrated to investigate the photo...

A muti-image encryption method based on QR code and singular value decomposition ghost imaging (LQSVDGI) is proposed. The target images are first preprocessed by logistic chaotic scrambling (LCS), and the scrambled images are synthesized into one image by XOR operation. QR encoding is performed for this image, and then the QR-coded image is encrypt...

Optical couplers play an important role in optical switches to split or combine light power in a predictable way. We proposed a novel scheme of photonic crystal (PhC) couplers relying on the unique characteristics of band-edge resonance. Stretched fundamental resonance can be excited in a square array of several periods to realize efficient transve...

Directional light manipulation plays an important role in the optical link and communication of nanotechnology and modern optics. In this work, we provide a practical solution for directional radiation based on drastic slow light resonance near the photonic band-edge. Unidirectional stretched oscillations in the modified resonator almost completely...

Inkjet‐printed perovskite quantum dot (PQD) color conversion films (CCFs) have great potentials for mini/micro‐LED displays because of their ultrahigh color purity, tunable emissions, high efficiency, and high‐resolution. However, current PQD inks mainly use expensive, toxic, and flammable organic substances as solvents. In this work, water is prop...

A dual-band microstrip patch antenna (MPA) based on a polarization conversion metasurface structure was designed. By etching the complementary split ring resonator (CSRR) on the ground plane, a new resonance frequency is generated. The proposed antenna is obtained through optimizing the structural parameters of CSRR. Compared with the antenna witho...

A hybrid cryptosystem based on plaintext-related ghost imaging and elliptic curve public-key cryptographic algorithm (ECC) is proposed in this paper. Thereinto, the ECC algorithm is used to protect and distribute session keys and the optical encryption system with session keys is used to encrypt and decrypt images. Thousands of phase-only mask keys...

The traditional ghost imaging encryption system has high pressure in key transmission and management for involving a series of random phase-only masks (POMs) as keys. And conventional ghost imaging encoding is vulnerable to a chosen-plaintext attack owing to the linearity of the system. To address these problems, a plaintext-related ghost imaging e...

Light redirection plays an important role in photonic integrated circuit system, which attracts much attention on account of thriving application prospects from microwave to visible frequency. By treating a two-dimensional photonic crystal array as a dielectric resonator with low effective index neff << 1, a new strategy of one-direction semi-enclo...

Ghost imaging can capture a scene without directly catching sight of the target, but in the case of high compression ratio, high-quality imaging is challenging at present. Here a ghost imaging method using weight coefficient matching based on discrete cosine transform (DCT) is proposed, in which the high-quality target images can be retrieved by ob...

Crack detection on metallic surfaces is important for the inspection of critical metallic devices. In this paper, a high-sensitivity near-field waveguide sensor loaded with a dielectric resonator for metallic crack detection is demonstrated. Both the numerical and experimental results reveal that this dielectric resonator-based waveguide sensor can...

Dielectric metasurfaces provide the new freedom to implement information encoding and image hiding with monolayer of artificial atoms instead of bulky optical components to enable wavelength, phase and polarization modulations. We proposed an optical encryption scheme by integrating the Visual Cyptography (VC) with the phase-encoding technique for...

A simple and novel slot-coupled dielectric resonator-based filter (DRF) with wideband performance is proposed, and the designed geometric parameters of the filter are discussed in detail. The proposed filter comprises a substrate, a microstrip line, and three dielectric resonators (DRs), which are positioned on the center of the corresponding slots...

An optical image watermarking method based on singular value decomposition ghost imaging (SVDGI) and a blind watermarking algorithm is proposed. The watermark image is first encrypted by an SVDGI system, then the encrypted watermark is embedded in the host image with the help of the watermark algorithm, which uses the block discrete cosine transfor...

Metasurface is emerging as an important platform to design various functional devices due to the superior capability in controlling amplitude, phase and polarization of light through its ultrathin engineering interface. A polarized-selective hologram of all-dielectric metasurface is proposed to reconstruct multiplexed holographic images on differen...

A multilevel image authentication method is proposed which is based on row scanning compressive ghost imaging and a hyperplane secret sharing algorithm. In the image encoding process, after the wavelet transform and Arnold transform for the certification image, through row scanning compressive ghost imaging, the ciphertext matrix can be first detec...

Ba (Zr0.2Ti0.8) O3-50% (Ba0.7Ca0.3) TiO3 (BZT-0.5BCT) ceramics with different doping contents of Pr³⁺ were prepared by the conventional solid-state reaction. The phase structure and crystallinity of the fabricated ceramics were investigated by X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. Photoluminescence (PL) emission s...

A computational ghost imaging encryption method based on fingerprint phase mask is proposed. In this work, we introduce one's fingerprint information into computational ghost imaging for the first time. The phase mask key in computational ghost imaging encryption is generated by a fingerprint image using digital holography method. As the phase key...

The singular value decomposition ghost imaging (SVDGI) is proposed to enhance the fidelity of computational ghost imaging (GI) by constructing a measurement matrix using singular value decomposition (SVD) transform. After SVD transform on a random matrix, the non-zero elements of singular value matrix are all made equal to 1.0, then the measurement...

A multiple-image encryption method via lifting wavelet transform (LWT) and XOR operation is proposed, which is based on a row scanning compressive ghost imaging scheme. In the encryption process, the scrambling operation is implemented for the sparse images transformed by LWT, then the XOR operation is performed on the scrambled images, and the res...

As interferometry is the highest precision distance measuring technique, we proposed a mechanism of single-beam interferometry employing all-dielectric photonic metamaterial with effective zero-index as a means of precise displacement measurement. This mechanism offers a straightforward method for performing optical range-finding over multi-wavelen...

A terahertz metasurface perfect absorber with multi-band performance is demonstrated. The absorber is composed of a ground plane and four split-ring resonators (SRRs) with different dimensions, separated by a dielectric spacer. The numerical simulation results illustrate that the proposed absorber has four distinct absorption peaks at resonance fre...

An optical image encryption method with multiple light paths is proposed based on compressive ghost imaging. In the encryption process, M random phase-only masks (POMs) are generated by means of logistic map algorithm, and these masks are then uploaded to the spatial light modulator (SLM). The collimated laser light is divided into several beams by...

A multiple-image encryption method is proposed that is based on row scanning compressive ghost imaging, (t, n) threshold secret sharing, and phase retrieval in the Fresnel domain. In the encryption process, after wavelet transform and Arnold transform of the target image, the ciphertext matrix can be first detected using a bucket detector. Based on...

A wideband metasurface filter based on complementary split-ring resonators (CSRR) has been prepared. The frequency and transmission bandwidth of the metasurface filters with different split widths are discussed. After analyzing the mechanism of the metasurface, the proposed metasurface filters are fabricated. The electromagnetic properties of the m...

The precise location of the Dirac-like point of a finite photonic crystal array with a triangular lattice can be identified easily from the transmittance spectrum of any output interface with the characteristic of a sharp cusp embedded in the extremum spectrum near the Dirac-like point. The transmission properties of the finite triangular lattice p...

The phenomena of the minimum transmittance spectrum or the maximum reflection spectrum located around the Dirac frequency have been observed to demonstrate the 1/L scaling law near the Dirac-like point through the finite ribbon structure. However, so far there is no effective way to identify the Dirac-like point accurately. In this work we provide...

A multiple-image encryption method that is based on a modified logistic map algorithm, compressive ghost imaging, and coordinate sampling is proposed. In the encryption process, random phase-only masks are first generated with the modified logistic map algorithm; multiple secret images are transformed to be sparsed by the 2-D discrete cosine transf...

A hierarchical multilevel authentication system for multiple-image based on phase retrieval and basic vector operations in the Fresnel domain is proposed, by which more certification images are iteratively encoded into multiple cascaded phase masks according to different hierarchical levels. Based on the secret sharing algorithm by basic vector dec...

A triple-image encryption method is proposed that is based on phase-truncated Fresnel transform (PTFT), basic vector composition, and XOR operation. In the encryption process, two random phase masks, with one each placed at the input plane and the transform plane, are generated by basic vector resolution operations over the first and the second pla...

A kind of multilevel authentication system for multiple-image based on modulated real part synthesis and iterative phase multiplexing in the Fresnel domain is proposed. In the design process of the low-level authentication system, a series of normalized real part information are iteratively generated by phase retrieval algorithm in the Fresnel doma...

Extraordinary transmission through a small aperture is of great interest. However, it faces a limitation that most of approaches can not realize the tunable transmission property, which is not benefit for the miniaturization of the microwave system. Here, we demonstrate a magnetically tunable broadband transmission through a small aperture. By plac...

A multiple-image authentication method with a cascaded multilevel architecture in the Fresnel domain is proposed, in which a synthetic encoded complex amplitude is first fabricated, and its real amplitude component is generated by iterative amplitude encoding, random sampling, and space multiplexing for the low-level certification images, while the...

A new kind of multilevel authentication system based on the (t, n) threshold secret sharing scheme and the iterative phase retrieval algorithm in Fresnel domain is proposed, in which, the first phase distribution iteratively generated is divided into n parts and delivered to n different participants, during high-level authentication, any t (t ≤ n)...

Ferrite metamaterials based on the negative permeability of ferromagnetic resonance in ferrites are of great interest. However, such metamaterials face a limitation that the ferromagnetic resonance can only take place while an external magnetic field applied. Here, we demonstrate a metamaterial based on permanent magnetic ferrite which exhibits not...

During the early years of research into metamaterials, some interest has shifted towards the realization of materials that exhibit zero or near-zero refractive index. A refractive index of zero implies that light enters a state of quasi-infinite phase velocity and infinite wavelength. Instead of strong resonance mechanism in metamaterials, the phys...

A study on improved light extraction efficiency (LEE) of LEDs with photonic crystals formed by holographic lithography (HL) was present. The propagation and extraction of light in LEDs were simulated using FDTD method for LED structures with top HL PC and embedded HL PC respectively. By optimizing the design parameters of the HL PC, the best value...

LED structures with the introducing of surface PC and planer micro cavity was described to improve the light extraction efficiency of LEDs. The distributions of guided modes propagated in LED were analyzed, and the modal extraction lengths were determined using high-resolution angle-resolved measurements in order to research the interaction of each...

This study proposes a novel graded photonic crystal structure that can be used to achieve asymmetric light propagation. This structure is obtained by changing the radius of a conventional square lattice photonic crystal. A higher contrast ratio is obtained by extending the numbers of the periods of the graded photonic crystal in the horizontal dire...

The effect of dual-negative refraction (DNR) in a photonic crystal (PhC) is demonstrated experimentally in X-band (8-12 GHz) for the first time. The two-dimensional PhC sample is made of highly pure Al2O3 ceramic cylinders close packed in air with a triangular lattice structure. The frequency regions of DNR are predicted by the analyses of wave vec...

We propose an asymmetric cryptosystem based on two-step phase-shifting interferometry (PSI) and elliptic curve (EC) public-key cryptographic algorithm, in which one image is encrypted to two interferograms by double random-phase encoding (DRPE) in Fresnel domain and two-step PSI, and the session keys such as geometrical parameters and pseudo-random...

Using of cascaded multimode interference waveguides in 2D photonic crystal power splitter are investigated by modeling and computation. Results show that with a five line defect waveguides and one pair of three line defect waveguides integrated, the total normalized transmission can be high as 94.9% with 30nm broad spectrum calculated and simulated...

Thermo-tunable negative refractive index (NRI) metamaterials with single- and dual-band based on ferrite have been designed and prepared; the scattering parameters of these metamaterials have been measured at various temperatures to demonstrate the thermo-tunable property. As the temperature increases, the peak value of passband decreases and the p...

An optical identity authentication scheme based on the elliptic curve digital signature algorithm (ECDSA) and phase retrieval algorithm (PRA) is proposed. In this scheme, a user’s certification image and the quick response code of the user identity’s keyed-hash message authentication code (HMAC) with added noise, serving as the amplitude and phase...

Due to the existence of photonic bandgap derived from the periodical dielectric structure in wavelength scale, many novel optical phenomena can be demonstrated in photonic crystals (PhCs). Anomalous propagation of electromagnetic waves in X-band is demonstrated experimentally in a two-dimensional triangular lattice PhC. The experimental measurement...

Zero phase delay of electromagnetic wave (EMW) transmission can be realized based on the wavefront modulation of photonic crystals (PhCs). When the phase velocity is controlled perpendicular to the group velocity with wavefronts (or phasefronts) parallel to the direction of energy flow, the phase will keep constant in transmission process despite o...

Anomalous optical transmission phenomena have ever been discovered in various metamaterials, which can be modulated more easily in Photonic crystals (PhCs). Compared with the regular PhCs composed of round rods closely packed in air, the equal frequency contours (EFC) of honeycomb lattice PhCs constituted by trigonal rods are more rounded and more...

A robust image watermarking scheme based on phase-shifting interferometry (PSI) and singular value decomposition (SVD) is proposed, in which, a grayscale image watermark is encrypted into multiple interferograms using the techniques of double random-phase encoding (DRPE) and PSI. By choosing the appropriate weighting factor, the interferograms are...

Plane-wave expansion method was employed to analyze the photonic band gap in two-dimensional silicon nitride photonic crystal. The effects of filling ratio and lattice structure type on the photonic band gap were studied. The results showed that two-dimensional dielectric cylinder type silicon nitride photonic crystal only has TE mode band gap, whi...

The transmission properties of electromagnetic wave (EMW) can be modulated by the periodic structure of photonic crystal (PhC) to bring many novel optical effects. The special distributions of equal frequency contours (EFCs) can be used to control the wavefront state and transmission direction of propagating wave in PhC with some special effects, s...

We propose a design of a highly litter (polarization beam splitter [PBS]) based on an indefinite medium. Due to the strong anisotropy, the splitting angle in the indefinite medium is controlled by the orientation angle and can reach to 90° which is much larger than that in a birefringence crystal (BC). Based on this property, a thin indefinite medi...

Multi-refraction effects with one polarization in a two-dimensional triangular photonic crystal (PhC) were systematically studied by theoretical analysis and numerical simulation. The more complicated refraction behaviors can be excited in the higher band regions based on the intricate undulation of one band or the overlap of different bands. A nov...

We propose a design of an extremely broad frequency band absorber based on destructive interference mechanism. Metamaterial of multilayered SRRs structure is used to realize a desirable refractive index dispersion spectrum, which can induce a successive anti-reflection in a wide frequency range. The corresponding high absorptance originates from th...

An air waveguide of left-handed photonic crystal (PhC) formed by holographic lithography is proposed. The symmetry mismatch between the incident wave and the Bloch modes of the holographic PhC is used to guide light efficiently. By properly designing the waveguide, backscattering loss can be significantly reduced. Due to the unique advantages of ho...

We have proposed a full-phase image encryption method based on double random-phase encoding in Fresnel domain and pixel random permutation (PRP) technique with the use of two-step phase-shifting interferometry (PSI) we reported recently, and verified the effectiveness of this method and its robustness against occlusion and noise attacks by a series...

A new kind of two-dimensional (2D) photonic crystals conforming to the 6-fold hybrid triangular configuration formed by holographic lithography is proposed. The relations between their photonic band gap (PBG) properties and their specific holographic designs for both the inverse and the normal structures are systematically investigated. Computation...

A novel single-channel color-image watermarking with digital-optics means based on phase-shifting interferometry (PSI) and a neighboring pixel value subtraction algorithm in the discrete-cosine-transform (DCT) domain is proposed. The converted two-dimensional indexed image matrix from an original color image is encrypted to four interferograms by a...

A new kind of two-dimensional 3-fold photonic crystal (PhC) conforming to the hybrid triangular configuration formed by holographic lithography (HL) is proposed, and the relation between its photonic band gap properties and its specific holographic design is systematically investigated. This structure can be conveniently produced using a multiple-b...

A theoretical investigation of the possible three-dimensional photonic crystal structures that can be created by holographic interference using the symmetric umbrella configuration of four plane waves is made. The irreducible Brillouin zones and the photonic band gap (PBG) properties of the possible resulting crystal lattices when the apex angle is...

A novel information security system based on multiple-phase retrieval by an iterative Fresnel-transform algorithm and pixel random permutation (PRP) technique is proposed. In this method a series of phase masks cascaded in free space are employed and the phase distributions of all the masks are adjusted simultaneously in each iteration. It can achi...