The model's verification error range sees a decrease of up to 53%. By improving the efficiency of OPC model construction, pattern coverage evaluation methods contribute favorably to the complete OPC recipe development process.

Due to their outstanding frequency selection abilities, frequency selective surfaces (FSSs), modern artificial materials, are proving highly valuable in various engineering applications. This paper introduces a flexible strain sensor utilizing FSS reflection characteristics. This sensor can conformally adhere to an object's surface, enduring mechanical deformation under load. Should the FSS structure be altered, the established working frequency will be displaced. By tracking the difference in electromagnetic capabilities, a real-time evaluation of the object's strain is achievable. Within this investigation, a 314 GHz FSS sensor was created. This sensor showcases an amplitude of -35 dB and exhibits favorable resonance behavior within the Ka-band. Remarkably, the FSS sensor possesses a quality factor of 162, showcasing its outstanding sensing performance. The sensor's role in detecting strain within the rocket engine case involved both statics and electromagnetic simulation. A 164% radial expansion of the engine case led to a roughly 200 MHz shift in the sensor's working frequency, showcasing an excellent linear relationship between frequency shift and deformation across a range of loads, thus enabling accurate case strain detection. Experimental data served as the basis for the uniaxial tensile test of the FSS sensor performed in this research. The sensitivity of the sensor reached 128 GHz/mm when the FSS was stretched between 0 and 3 mm during the test. Consequently, the FSS sensor exhibits a high degree of sensitivity coupled with robust mechanical properties, thus validating the practical utility of the FSS structure presented in this article. selleck chemicals This field has a broad expanse for further development.

The use of a low-speed on-off-keying (OOK) optical supervisory channel (OSC) in long-haul, high-speed dense wavelength division multiplexing (DWDM) coherent systems results in extra nonlinear phase noise caused by cross-phase modulation (XPM), which constrains the transmission distance. This paper introduces a straightforward OSC coding approach for mitigating the nonlinear phase noise stemming from OSC. selleck chemicals The up-conversion of the OSC signal's baseband, achieved through the split-step Manakov equation's solution, is strategically executed outside the walk-off term's passband to minimize XPM phase noise spectral density. Experimental transmission of 400G signals over 1280 km yields an optical signal-to-noise ratio (OSNR) budget enhancement of 0.96 dB, achieving a performance almost equal to that without optical signal conditioning.

Highly efficient mid-infrared quasi-parametric chirped-pulse amplification (QPCPA) is numerically demonstrated using a recently developed Sm3+-doped La3Ga55Nb05O14 (SmLGN) crystal. At a pump wavelength of approximately 1 meter, QPCPA for femtosecond signal pulses centered at 35 or 50 nanometers benefits from the broadband absorption of Sm3+ in idler pulses, achieving a conversion efficiency approaching the quantum limit. Mid-infrared QPCPA demonstrates robustness against phase-mismatch and pump-intensity variation precisely because of the suppression of back conversion. Intense laser pulses, currently well-developed at 1 meter wavelength, will be efficiently transformed into mid-infrared ultrashort pulses via the SmLGN-based QPCPA.

This manuscript investigates a narrow linewidth fiber amplifier, realized using a confined-doped fiber, evaluating its power scaling capabilities and beam quality preservation. The confined-doped fiber, with its large mode area and precisely controlled Yb-doped region within the core, successfully managed the interplay between stimulated Brillouin scattering (SBS) and transverse mode instability (TMI). Employing a combination of confined-doped fiber, near-rectangular spectral injection, and 915 nm pumping, a 1007 W signal laser is realized, showcasing a linewidth of only 128 GHz. This research, to the best of our knowledge, has yielded the first demonstration exceeding the kilowatt power level for all-fiber lasers that exhibit GHz-level spectral linewidth. It could provide a valuable benchmark for synchronizing spectral linewidth control with the suppression of stimulated Brillouin scattering and thermal management problems in high-power, narrow linewidth fiber lasers.

For a high-performance vector torsion sensor, we suggest an in-fiber Mach-Zehnder interferometer (MZI) architecture. This architecture comprises a straight waveguide inscribed within the core-cladding boundary of the single-mode fiber (SMF) with a single laser inscription step using a femtosecond laser. The 5-millimeter in-fiber MZI length, coupled with a fabrication time under one minute, allows for rapid prototyping. The device's asymmetric design leads to a high degree of polarization dependence, which is manifest as a prominent polarization-dependent dip within the transmission spectrum. The twisting of the fiber alters the polarization state of the incoming light to the in-fiber MZI, thereby allowing torsion sensing through the analysis of the polarization-dependent dip. Demodulation of torsion is achievable through both the wavelength and intensity variations within the dip, and vector torsion sensing is accomplished by meticulously adjusting the polarization state of the incident light. Employing intensity modulation techniques, the torsion sensitivity can scale to an impressive 576396 dB/(rad/mm). The responsiveness of dip intensity to alterations in strain and temperature is weak. The incorporated MZI design, situated within the fiber, keeps the fiber's coating intact, thereby sustaining the complete fiber's ruggedness.

In this paper, the first implementation of a novel privacy protection method for 3D point cloud classification is presented, based on an optical chaotic encryption scheme. This directly addresses the privacy and security concerns. The study of mutually coupled spin-polarized vertical-cavity surface-emitting lasers (MC-SPVCSELs) influenced by double optical feedback (DOF) is focused on generating optical chaos, which is leveraged for the encryption of 3D point clouds through the use of permutation and diffusion processes. Nonlinear dynamics and complexity results affirm that MC-SPVCSELs equipped with degrees of freedom possess high chaotic complexity and can generate a tremendously large key space. By means of the suggested scheme, the ModelNet40 dataset's 40 object categories' test sets were encrypted and decrypted, and the classification results for the original, encrypted, and decrypted 3D point clouds were exhaustively recorded using PointNet++ . Puzzlingly, the class-wise accuracies of the encrypted point cloud are virtually zero in almost every instance, with the sole exception being the plant category, achieving an extraordinary accuracy of one million percent. This reveals the encrypted point cloud's unclassifiable and unidentified nature. In terms of accuracy, the decrypted classes' performance is virtually equivalent to that of the original classes. The classification findings thus validate the practical application and exceptional performance of the proposed privacy protection strategy. The encryption and decryption results, in particular, demonstrate a lack of clarity in the encrypted point cloud images, rendering them indistinguishable, in contrast to the decrypted point cloud images, which are precisely the same as the original ones. This paper's security analysis is bolstered by a study of the geometrical characteristics within 3D point clouds. A final security analysis validates that the proposed privacy-protection approach achieves a high security level, safeguarding privacy effectively within the context of 3D point cloud classification.

The quantized photonic spin Hall effect (PSHE), anticipated in a strained graphene-substrate structure, is predicted to be elicited by a sub-Tesla external magnetic field, an extraordinarily diminutive field compared to the sub-Tesla magnetic field requirement for its occurrence in the conventional graphene system. Quantized behaviors of in-plane and transverse spin-dependent splittings in the PSHE are demonstrably different, exhibiting a strong relationship with reflection coefficients. Whereas quantized photo-excited states (PSHE) in a typical graphene substrate are formed through the splitting of real Landau levels, the quantized PSHE in a strained substrate is a consequence of pseudo-Landau level splitting, occurring due to a pseudo-magnetic field. Furthermore, the lifting of valley degeneracy in the n=0 pseudo-Landau levels is a consequence of the application of sub-Tesla external magnetic fields. The system's pseudo-Brewster angles exhibit quantization in response to shifts in Fermi energy. The sub-Tesla external magnetic field and the PSHE present as quantized peaks in the vicinity of these angles. The giant quantized PSHE is foreseen to enable direct optical measurements of quantized conductivities and pseudo-Landau levels in the monolayer strained graphene.

In the field of optical communication, environmental monitoring, and intelligent recognition systems, polarization-sensitive narrowband photodetection at near-infrared (NIR) wavelengths has become significantly important. The current narrowband spectroscopy method, however, is largely reliant on added filters or bulky spectrometers, which is contrary to the goal of achieving miniaturization within on-chip integration. Functional photodetection has been afforded a novel solution through recent advancements in topological phenomena, particularly the optical Tamm state (OTS). We have successfully developed and experimentally demonstrated, to the best of our knowledge, the first device based on a 2D material, graphene. selleck chemicals Polarization-sensitive narrowband infrared photodetection in OTS-coupled graphene devices is demonstrated here, their design informed by the finite-difference time-domain (FDTD) approach. Empowered by the tunable Tamm state, the devices manifest a narrowband response at NIR wavelengths. The response peak demonstrates a full width at half maximum (FWHM) of 100nm, however, increasing the periods of the dielectric distributed Bragg reflector (DBR) presents a pathway to an ultra-narrow FWHM of 10nm.