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#author("2024-12-07T04:42:42+09:00","","") We develop a multimodal imaging platform, combining depth-resolved scattering contrast from spectral-domain optical coherence tomography (SD-OCT) with complementary, non-contact absorption contrast using photoacoustic remote sensing (PARS) microscopy. The system provides a widefield OCT mode using a telecentric scan lens, and a high-resolution, dual-contrast mode using a 0.26 numerical aperture apochromatic objective. An interlaced acquisition approach is used to achieve simultaneous, co-registered imaging. The SD-OCT modality provides a 9.7 µm axial resolution. Comprehensive in vivo imaging of a nude mouse ear is demonstrated, with the SD-OCT scattering intensity revealing dermal morphology, and PARS microscopy providing a map of microvasculature.We present a new, to the best of our knowledge, method to perform acousto-optic imaging based on a spatiotemporal structuration of long-duration acoustic plane waves. This approach is particularly relevant when using detectors with long integration times. We show how it is possible to reconstruct an image by measuring its two-dimensional Fourier components. A proof of concept is presented using a photorefractive detection scheme, demonstrating equal performances to direct imaging. The overall acquisition time is compatible with medical monitoring applications.The combination of light sheet fluorescence microscopy (LSFM) and the optical clearing method can achieve fast three-dimensional high-resolution imaging. However, there is an essential contradiction between the field of view (FoV) and spatial resolution. Also, aberration and scattering still exist after tissue clearing, which seriously limits the imaging depth of LSFM. Here we propose a Schwartz modulation method and implement it in LSFM based on a quasi-Bessel beam to enlarge the imaging FoV without sacrificing its spatial resolution. https://www.selleckchem.com/products/Gefitinib.html The simulation results show that the FoV of the LSFM is enlarged by a factor of 1.73 compared to the Bessel beam. The capability of extremely fast decay along the optical axis makes Schwartz modulation more tolerant for scattering, indicating potential applications for deep tissue imaging. Also, the capability of sidelobe suppression effectively decreases unnecessary fluorescence excitation and photobleaching.Due to the utilization of overlapped dipole resonances, traditional Huygens' metasurfaces suffer from dipole interactions. In this Letter, we propose a design of phase-gradient Huygens' metasurface based on the quadrupole resonances excited in the cross-shaped structures. The quadrupole resonances are theoretically shown insensitive to the quadrupole interactions. Benefiting from this intrinsic property, the proposed metasurface can well suppress element interaction influence and exhibits some impressive properties, including the ability to suppress high diffraction orders, tunable anomalous refractive angles, and high transmission efficiency. The numerical results show promising potential for quadrupole resonances to be applied in advanced Huygens' metasurface designs.Self-powered photodetectors have demonstrated potential for developing future wireless and implantable devices. Herein, we present a self-powered UV photodetector with an ultrahigh photoresponse based on vertically oriented and high crystalline quality n-type GaN nanorod arrays poly(methyl methacrylate)/p-Si heterojunction. Benefiting from the highly efficient separation and transport of photoexcited electron-hole pairs, significant improvements in photoresponsivity are experimentally obtained. In a zero-biased self-powered detection mode, a 6.7AW-1 responsivity and 2.68×1013 Jones detectivity are achieved under 355 nm light illumination, and the response time is as low as 0.29/3.07 ms (rise/fall times).In this work, we demonstrate a novel high-power vertical-cavity surface-emitting laser (VCSEL) array with highly single-mode (SM) and single-polarized output performance without significantly increasing the intra-cavity loss and threshold current (Ith). By combining a low-loss zinc-diffusion aperture with an electroplated copper substrate, we can obtain a highly SM output (side mode suppression ratio >50dB) with a very narrow divergence angle (1/e2∼10∘) under high output power (3.1 W; 1% duty cycle) and sustain a single polarization state, with a polarization suppression ratio of around 9 dB, under the full range of bias currents. Compared to the reference device without the copper substrate, the demonstrated array can not only switch the output optical spectra from quasi-SM to highly SM but also maintain a close threshold current value (Ith 0.8 versus 0.7 mA per unit device) and slope efficiency. The enhancement in fundamental mode selectivity of our VCSEL structure can be attributed to the single-polarized lasing mode induced by tensile strain, which is caused by the electroplated copper substrate, as verified by the double-crystal x-ray measurement results.Real-time measurement of ultrafast pulses together with high temporal resolution and long recording length is an urgent requirement of all optical communication systems and nonlinear science. Here, external motion dynamics of soliton pairs in mode-locking ultrafast fiber lasers can be single-shot characterized with long recording length, by using an asynchronous four-wave-mixing (FWM)-based temporal magnifier (AFTM) system. Recording length of more than one thousand roundtrips can be achieved through the AFTM system. Temporal propagation dynamics of soliton pairs with tunable separations are observed, revealing that soliton pairs with narrower separation display vibration-like dynamics, while the two solitons with wider separation remain relatively unchanged. We believe our results will provide a promising solution for real-time measurement of ultrafast pulse and can offer novel insights for ultrafast transient dynamics in nonlinear optics.An all-optical tunable filter based on a fiber Bragg grating (FBG) inscribed in a self-heated silica/silicone composite fiber is demonstrated. A thin silicone film is coated inside the suspended core fiber), which acts as the silicone cladding. A periodic refractive index modulation is inscribed in the silicone cladding by UV irradiation. Silicone is an organic material whose optical properties are different than silica, which leads to interesting applications. The high thermo-optic properties are studied and applied here. A 1550 nm pump laser is utilized to heat the silicone grating where a wavelength shift is observed for the gratings when subjected to different pump powers. Experimental results indicate a wavelength tuning coefficient of -0.128nm/mW with a response time of 0.5 s to obtain a wavelength shift of 1 nm under periodic pump light. The new design of this miniature all-optical filter is cost-effective and can potentially be adhered in optical fiber sensing and communication systems.
