Article
Nanoscience & Nanotechnology
Shan Yin, Yuting Chen, Baogang Quan, Songyi Liu, Wei Huang, Meng Liu, Wentao Zhang, Jiaguang Han
Summary: This paper demonstrates novel polarization-sensitive transmission effects in terahertz chiral metasurfaces. The asymmetrical transmission for circularly polarized state is observed in the chiral metasurfaces through circular cross-polarization conversion spectra and circular conversion dichroism (CCD). The chiroptical activities are found to be affected by the coupling between the wire and split ring resonator (SRR) in the terahertz metasurfaces.
Article
Optics
Jiahao Guo, Jiubin Tan, Pengcheng Hu, Steven T. Cundiff
Summary: Light propagation in arrays of AlxGa1-xAs waveguides was studied, with the power coupling constant between adjacent waveguides measured precisely. The polarization dependence of coupling constants was observed due to asymmetric effective refractive index between linearly polarized modes. Through careful geometric design, comparable coupling constants were achieved in three waveguide arrays with different structures.
Article
Optics
Wei Huang, Shi-Ting Cao, Wentao Zhang, Shan Yin, Jiaguang Han
Summary: This paper investigates the resonant frequency shifting of metamaterials caused by the coupling effect. The split ring resonators (SRRs) are used to generate magnetic dipoles by decreasing the distance between them, thus increasing the coupling. The authors analyze the difference in resonant frequency shifting between two scenarios and verify their results through simulations and experiments. Additionally, bound states in the continuum (BIC) are established using two slightly different SRRs, and the resonant frequency shifting of BIC follows the predicted rule.
OPTICS AND LASER TECHNOLOGY
(2024)
Article
Optics
J. Schulz, C. Joerg, G. von Freymann
Summary: This study experimentally demonstrates that the next-nearest-neighbor coupling in a waveguide array can be naturally negative. By fabricating dielectric zig-zag shaped waveguide arrays and adjusting the angle of the zig-zag shape, it is possible to tune the coupling ratios between positive and negative values, as well as reduce the impact of the coupling to zero at certain angles. The existence of negative couplings is confirmed experimentally and the improved accuracy of a refined tight-binding model is shown. These findings are also important for studying other discrete systems where the tight-binding model is commonly used.
Article
Materials Science, Multidisciplinary
Y. Liang, Q. Gaimard, V Klimov, A. Uskov, H. Benisty, A. Ramdane, A. Lupu
Summary: By modulating the gain and loss levels of the medium, high-contrast tunable metasurfaces can be efficiently implemented, providing practical operability for the design model.
Article
Materials Science, Multidisciplinary
S. V. Andreev
Summary: We present a theoretical approach to the problem of two-dimensional fermion pairing under spin-orbit coupling and Zeeman interaction with an external magnetic field. Our theory maps onto the two-channel Fano-Anderson model of a spinless resonant p-wave superfluid in the strong-coupling limit of the many-body fermion system at zero temperature.
Article
Multidisciplinary Sciences
Si-Si Wang, Kangkang Li, Yi-Ming Dai, Hui-Hui Wang, Yi-Cai Zhang, Yan-Yang Zhang
Summary: We study the impact of disorder and shielding on quantum transports in a two-dimensional system with all-to-all long range hopping. We find that in weak disorder, the cooperative shielding leads to the formation of perfect conducting channels similar to those in the short range model. As the disorder increases, the conductance becomes larger and more fluctuating, indicating the breaking of shielding and the contribution of long range hopping. The wavefunctions are not completely localized and exhibit a hybrid feature of localization and delocalization with a fractal dimension smaller than 2.
SCIENTIFIC REPORTS
(2023)
Article
Physics, Multidisciplinary
Martin-Isbjorn Trappe, Piotr T. Grochowski, Jun Hao Hue, Tomasz Karpiuk, Kazimierz Rzazewski
Summary: We predict the phase separations of two-dimensional Fermi gases with repulsive contact-type interactions between two spin components. The universal transition from the paramagnetic state at small repulsive interactions toward ferromagnetic density profiles at large interaction strengths is revealed, with intricate particle-number dependent phases in between. Our employed corrections to the bare contact interaction energy and especially to the Thomas-Fermi kinetic energy functional are necessary for reliably predicting properties of trapped mesoscopic Fermi gases.
NEW JOURNAL OF PHYSICS
(2021)
Article
Physics, Mathematical
Michele Caraglio, Lukas Schrack, Gerhard Jung, Thomas Franosch
Summary: In this study, the numerical schemes for evaluating the MCT functional within the glass transition theory were reconsidered. Nonuniform discretizations of wave number were proposed to decrease the number of grid points without losing accuracy. The modified integration scheme on the new grids showed significant performance improvements when solving the MCT equations for mono-disperse hard disks and hard spheres.
COMMUNICATIONS IN COMPUTATIONAL PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Yun-Tak Oh, Jintae Kim, Jung Hoon Han
Summary: In this study, a rank-2 toric code Hamiltonian is constructed and it is found that the quasiparticles in this model exhibit unusual braiding statistics, capturing the total dipole moment of the particles involved in the braiding. An emergent vector potential is introduced to interpret this dipolar braiding statistics.
Article
Engineering, Electrical & Electronic
Anton S. Kupriianov, Alexander Trubin, Vladimir R. Tuz
Summary: The importance of the coupled-mode theory in electromagnetic theory is discussed, and practical formulas for calculating the mutual coupling coefficient between dielectric resonators are presented. The correctness of the formulas is validated through numerical simulations, making them useful for analyzing the performance of dielectric antennas and metasurfaces.
JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS
(2022)
Article
Chemistry, Physical
Yao Xuan, Kris T. Delaney, Hector D. Ceniceros, Glenn H. Fredrickson
Summary: This study presents a computational framework that combines deep learning with self-consistent field theory simulations to accelerate the exploration of parameter space for block copolymers. Several innovations and improvements are proposed, including the use of a Sobolev space-trained convolutional neural network to handle the dimension increase of monomer density fields and the introduction of a generative adversarial network (GAN) to predict saddle point density fields. The framework demonstrates its potential in accelerating the discovery of polymer nanostructures through the successful application to 2D cell size optimization.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Mathematics
Hung Tran, Yifeng Yu
Summary: We study the effective front associated with first-order front propagations in two dimensions with continuous coefficients. Our main result shows that the boundary of the effective front is differentiable at every irrational point. This is the first nontrivial property of the effective fronts in the continuous setting.
INTERNATIONAL MATHEMATICS RESEARCH NOTICES
(2023)
Article
Optics
Silas R. Beane, Gianluca Bertaina, Roland C. Farrell, William R. Marshall
Summary: We study the ultracold and weakly coupled Fermi gas in two spatial dimensions using an effective field theory framework. It is found that the universal corrections to the energy density at two orders of interaction strength do not agree with Monte Carlo simulations in the weak-coupling regime. We obtain universal corrections to three orders of interaction strength, which provide agreement between theory and simulation. We also consider the scale ambiguity associated with the renormalization of singular contact interactions, and calculate nonuniversal contributions to the energy density.
Article
Chemistry, Multidisciplinary
Zhaolong Cao, Jianfa Chen, Shaozhi Deng, Huanjun Chen
Summary: Understanding the physical origins of chiroptical responses in artificial optically active media is crucial for developing high-performance circular dichroism spectroscopic techniques. In this study, a biorthogonal approach based on temporal coupled-mode theory is presented to explain the underlying physics of chiral metasurfaces. It is found that the intrinsic chirality of coupled chiral nanocavities arises from the asymmetric coupling between interlayer cross-polarized resonant modes and coherent interference between doubly degenerate states.
