Optics letters最新文献

Stereoscopic phase measuring deflectometry (stereo-PMD) is widely used in the measurement of specular surfaces due to its superiority in solving the height-slope ambiguity and model-free nature compared with mono-PMD. Reconstruction in stereo-PMD starts with the search for spatial points based on normal consistency criterion to specify the position of slope sampling plane (SSP), but the results are not necessarily unique. In this work, for stereo-PMD, an iterative reconstruction method is proposed to eliminate the point cloud search and positional consideration of SSP. Instead, the constraint of specular regions consistency is used to supersede the normal consistency to dynamically optimize the position of SSP. Experimental results demonstrate the improvement over 80% in low-order accuracy and 33% in noise robustness.

Size effects limit the application of GaN-based Micro-LEDs in advanced display technologies. To mitigate these size effects, a mesa-structured Micro-LED with a full m-faceted hexagonal facet is proposed, unlike the traditional square structure. Results show that, through the synergistic effect of crystal facet selection and structural optimization, the full m-plane hexagonal Micro-LED is less affected by dry etching and sidewalls, thus significantly improving its photoelectric properties. With decreasing size, the peak EQE of the hexagonal Micro-LED decreases from 15.95% to 14.76%, while the peak EQE of the square Micro-LED decreases from 15.67% to 13.96%. This work provides a new, to the best of our knowledge, fabrication process for suppressing size effects and developing small-sized, high-efficiency Micro-LEDs.

In this Letter, Yb-doped Al₂O₃-P₂O₅-B₂O₃-SiO₂ fibers are first studied with different B₂O₃ doping levels to suppress stimulated Brillouin scattering (SBS). It is revealed that by heavy B₂O₃ doping, the Brillouin gain spectrum broadens, and the gain coefficient decreases substantially, which leads to a significant SBS suppression effect. For Yb-doped fibers (YDFs) of 6.43 mole% B₂O₃, the Brillouin gain coefficient suppression ratio improves by more than 5.0 dB, and the SBS threshold of single-frequency (SF) laser emission enhances by 4.87 times, compared to YDF of weak B₂O₃ doping. Based on the optimal B₂O₃-doped YDF with a step-index 20-μm-diameter core, high-beam-quality single-frequency laser emission has been achieved with 311.7 W output power. The laser linewidth is measured to be 2.9 kHz. The beam quality M² factor is 1.20, and the fundamental mode ratio is calculated to be above 97% in the output beam at the maximum output. This work provides an effective material-based strategy for power scaling of single-frequency fiber lasers with strong potential for practical applications.

This erratum updates the authorship and funding information of Opt. Lett.49, 1560 (2024)10.1364/OL.520008. Specifically, an author has been added to the author list, and funding acknowledgements have been updated. These changes do not affect the scientific results or conclusions of the paper.

Although glass-based long-persistent luminescence (LPL) materials offer superior transparency and integration capability compared with conventional phosphors, their emission has been predominantly restricted to the blue-green region, leaving warm-color LPL largely unexplored. In this work, Mn²⁺-doped borosilicate glasses with warm-color LPL were prepared using the high-temperature melting method, and tunable LPL behaviors with dual-modes were achieved under 365/254 nm excitation. Under 365 nm excitation, the LPL color can be continuously tuned from yellow to red with enhanced LPL intensity, whereas under 254 nm excitation, a nonmonotonic intensity evolution with bright orange LPL is observed. Combined analyses reveal the dual role of Mn²⁺ ions as both the orange-red emitting center and an effective trap-modulating species, leading to excitation-dependent LPL behaviors. This study promotes the application of multi-mode and secure warm-color LPL glasses in optical information storage.

We propose that the symmetry-breaking bifurcation of coupled topological edge states (CTESs) can be used as a general principle for achieving spontaneous symmetry breaking (SSB) in a nonlinear topological lattice. Using an optical resonator array composed of two Su-Schrieffer-Heeger (SSH) chains as an example, we find that as the nonlinearity strength increases, the symmetric CTESs undergo a supercritical bifurcation. Beyond the critical threshold, the originally stable symmetric state becomes unstable, leading to the formation of a pair of stable asymmetric states. Both sides of the symmetric CTESs exhibit sublattice polarization, while the side of the asymmetric CTESs that is predominantly occupied demonstrates stronger sublattice polarization. We further find that as interchain coupling increases, the frequency range for stable symmetric CTESs expands, while the frequency range for stable asymmetric CTESs decreases. Our work provides a universal mechanism for realizing SSB in nonlinear topological lattices.

Violet-light emitters serve critical functions across diverse domains, spanning biology, photopolymerization processes, and anti-counterfeiting solutions. In perovskite materials, the partial substitution of Pb²⁺ with Sr²⁺ at the B-site enables the preparation of perovskite films with continuously tunable emission from green to violet. These films exhibit excellent photoluminescence quantum yields, highlighting the potential of Sr-based metal halide perovskites for violet-emitting applications. However, excessive introduction of Sr²⁺ increases the carrier effective mass, resulting in a significant decline in carrier mobility. Herein, we demonstrate that K⁺ doping optimizes the carrier effective mass, which contributes to a notable enhancement in carrier mobility. Density functional theory (DFT) calculations indicate that the carrier mobility in K⁺-modified perovskite is approximately 1.5 times that of the pristine perovskite. Moreover, the disparity between electron and hole mobilities is reduced, indicating a more balanced trend in charge transport properties. The K⁺-modified device exhibited a stable emission peak at 420 nm and achieved a maximum external quantum efficiency (EQE) of 0.35%, representing high performance among violet perovskite light-emitting diode (PeLEDs). This work presents a facile strategy for fabricating high-performance violet PeLEDs with enhanced efficiency and stability.

An optical transfer delay (OTD) measurement method based on the vernier scale readout principle is proposed to simultaneously enhance the measurement range and accuracy. In this work, two detuned microwave signals modulate an optical carrier, which is then injected into a high-precision swept optical delay line (ODL)-integrated optical-carrier microwave interferometer. This process generates two power-delay profile diagrams exhibiting slightly detuned delay characteristics, from which the target OTD can be precisely extracted via the vernier scale readout principle. Simulation and experimental studies were conducted to evaluate the proposal.

Current holographic data storage (HDS) systems mainly use amplitude and phase modulation for data encoding, while polarization is limited to multi-channel multiplexing, often causing operational difficulties and system complexity. To solve this, we propose a new, to the best of our knowledge, method that combines multiple polarization states into a single data page. Using polarization holography theory, we developed a reconstruction method capable of accurately reconstructing data pages with different polarization information. This method encodes data directly through multiple polarization states on one page. Decoding is simplified using a single 45° linear polarizer before the camera, enabling efficient distinction between different polarization states. Experiments show zero-error decoding for 2-, 3-, and 4-level polarization data pages. This research simplifies system design, reduces operation complexity, and expands HDS encoding dimensions, offering a new technical approach for practical high-density holographic storage.

Rydberg atom-based precision terahertz (THz) metrology has advanced rapidly in recent years. However, its electric-field sensitivity remains significantly lower than that of state-of-the-art THz receivers, thereby limiting its potential for practical applications. In this work, we enhance the sensitivity of a Rydberg atom-based THz heterodyne receiver at 0.3 THz by employing a 3 × 3 laser-beam array, yielding a 7.6 dB improvement over a single-beam configuration. The achieved electric-field sensitivity reaches 35.8±1.4 nV cm^-1 Hz^-1/2, approaching the performance of an ideal λ/2 metallic antenna. A minimum-detectable power of -149 dBm is achieved at a 1-Hz bandwidth. Our results suggest a promising approach for future THz radar and communication applications.