Random Fiber Lasers

A multimode-fiber-mediated random fiber laser with 100+ watt output power was demonstrated for speckle-free imaging, as presented by Shanshan Wang, Weili Zhang, Yunjiang Rao, and co-workers in article number 2100390. A random laser combined with multimode fiber provides a powerful platform to realize advanced fiber lasers with controllable spatial characteristics, which is of great significance for applications of imaging and sensing.

ZrTe₃ Nanoparticles

In article number 2100237, Zhanqiang Hui, Dongdong Han, and co-workers demonstrate a passive harmonic mode-locking erbium-doped fiber laser employing a ZrTe₃ nanoparticle-based saturable absorber. At a pump power of 310 mW, an ultrashort pulse with a repetition rate of 483.1 MHz (corresponding to 83 order harmonic mode locking) is obtained. It reveals that ZrTe₃ nanoparticles are excellent photonic materials and have great application potential in ultrafast photonics.

Custom fields with singularities have extensive applications. This review summarizes singular fields formed by the transmission metasurfaces. Optical vortices, vector fields and hybrid vector fields generated through the amplitude, phase and polarization modulation of tiny holes are provided. This review demonstrates the powerful light manipulation abilities of metasurfaces and promotes the applications of singular fields formed by metasurfaces.

The supercollimation effect is a far-field phenomenon occurring in 3D photonic crystals made from concentric gratings. A minidevice can concentrate plane waves on the optical axis with great efficiency if the right lattice is achieved.

With first-principles, the electronic and magnetic properties of MSi₂N₄ (M = V, Cr) monolayers are investigated under the effects of strain engineering. Their magnetic configurations are effectively tuned via uniaxial and biaxial tensile strain of in-plane lattice vectors. VSi₂N₄ exhibits half-metallic ferromagnetic character with a high magnetic ordering temperature of 285 K, whereas CrSi₂N₄ is prone to be AFM.

In this article, an effective method is proposed to increase high-dimensional entangled information capacity and long-distance communication by spontaneous six-wave and eight-wave mixing processes in ⁸⁵Rb atomic vapor. The competition and coexistence is investigated between the linear and nonlinear optical responses of tri- and quadphotons in multidressing fields, such as group delay regime, Rabi oscillation regime, and transition process.

For 1D rhombus lattices, when intracell hopping amplitudes are the same, degenerate topological edge states appear. Changes in intracell hopping amplitudes lead to different types of edge states and the robustness of edge states to disorder are different. The introduction of magnetic flux modulates the energy band structures and opens new gaps; it also induces edge states with their different topological properties.

By exploiting the noncommutativity and interaction between quantum states encoding system information and unitary block-diagonal matrices encoding interfering paths and phase shifts, multi-path interference is quantified via quantum coherence, which in turn is quantified in terms of a generalization of the Wigner–Yanase skew information. This reveals an intrinsic connection between interference and quantum coherence from an information-theoretic perspective.

Lattices are periodic arrangements of points in n-dimensional space. How should the grid be arranged, to minimize the average squared distance to the closest point? Lattices studied during the past century appear to provide the best solutions for $n\le 8$. In this work, in $n=9$ dimensions, a non-classical “laminated” lattice is found, shown to be better, and conjectured to be optimal.

The process of information loss from quantum gravity in a dilaton black hole is modeled by the quantum channel beyond single mode approximation. The quantumness for Dirac particles escaping from the outside region can be preserved to a high extent under the circumstance of small dilaton fields. The external fluctuations contribute to the protection of relativistic quantum information.

A system based on a quantum-ring in between of two topological superconductors hosting Majorana bound states allows to observe topological patterns in the spectrum due to the hybridization of the Majoranas in the quantum-ring. Hence, these topological patterns could be detected with persistent and Josephson currents.

A high-power multimode random fiber laser with high spectral density and high efficiency is demonstrated for speckle-free imaging, which can achieve a maximum output power of 100.6 W and speckle contrast of 0.037. The quality of speckle-free imaging is improved by increasing the power of the laser as its spatial coherence decreases with increasing excited modes in the multimode fiber.

In this study, a saturable absorber (SA) based on ZrTe₃ is used in a harmonic passive mode-locking erbium-doped fiber laser for the first time. The results show that when the pump power is 310 mW, a high-repetition-rate of 483.1 MHz is achieved. The pulse width, 3 dB optical spectral width, and SNR are 1.302 ps, 3.14 nm, and 67 dB, respectively.

Here, a novel, single-layer, and low-profile multifunction coding metasurface based on frequency and polarization multiplexing is proposed. Numerical and experimental results demonstrate that the proposed coding metasurface can achieve the functions of four-channel wavefront manipulations including beam splitting, abnormal deflection, vortex beam generation, and radar cross section (RCS) reduction at two frequencies under both linearly orthogonal polarization excitations.

The present work is the first report expounding the potential of complex network constructed from the specklegram of thin films in unveiling the intrafilm thermal-induced dynamics. The heat map and co-occurrence matrix analyses are also employed to understand the dynamics in RF sputtered molybdenum oxide film. The study proposes a sensitive tool based on graph features for thin film analysis.