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We demonstrate a phase-shifted Bragg grating waveguide (PS-BGW) fabricated by a direct laser writing technique via two-photon polymerization as a high-frequency ultrasonic sensor. The PS-BGW device has a cross-sectional area of 1.5 μm×2 μm, and the grating length is about 100 μm. The optical resonant spectrum is investigated numerically and experimentally. The result shows that the fabricated device with a grating depth of 250 nm and a quarter wave phase lead to a 20-nm stopband and a 0.085-nm full-linewidth of the transmission notch, making it suitable for photonic sensing applications. Here, the PS-BGW device is demonstrated for the detection of acoustic waves, which can cause strain or deformation of the device and lead to a shift in the resonance wavelength. The sensitivity and the limitations of the device for ultrasound detection are also investigated.
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http://dx.doi.org/10.1364/OL.44.003817 | DOI Listing |
Int Urol Nephrol
September 2025
Department of Urology, Brigham and Women's Hospital, Harvard Medical School, 45 Francis St, ASB II-3, Boston, MA, 02115, USA.
Background: With the advancement of MR-based imaging, prostate cancer ablative therapies have seen increased interest to reduce complications of prostate cancer treatment. Although less invasive, they do carry procedural risks, including rectal injury. To date, the medicolegal aspects of ablative therapy remain underexplored.
View Article and Find Full Text PDFJ Refract Surg
September 2025
American University of Beirut Ophthalmology Department, Beirut, Lebanon.
Purpose: To investigate eye movement dynamics during excimer laser ablation, specifically femtosecond laser-assisted in situ keratomileusis (FS-LASIK), and compare movement patterns between the right eye (always operated on first) and the left eye (operated on second), analyzing direction, magnitude, and temporal changes.
Methods: A retrospective analysis was conducted on 92 eyes from 46 patients who underwent FS-LASIK with the SCHWIND AMARIS system (SCHWIND eye-tech-solutions). Eye-tracking data were collected to record horizontal and vertical directional movements; variability was assessed using standardized metrics.
Chem Asian J
September 2025
School of Science and Engineering, Shenzhen Institute of Molecular Aggregate Science and Engineering, The Chinese University of Hong Kong, Shenzhen (CUHK-Shenzhen), Shenzhen, 518172, China.
Organic high-temperature photothermal materials (T > 100 °C) have demonstrated significant application values because of their ability to exceed the temperature limits of traditional organic photothermal materials, enabling spatiotemporally controllable long-distance heating and high-temperature conversion of laser or sunlight. In this review, we summarize the recent progress in organic high-temperature photothermal materials, mainly including organic small molecule and polymer materials. Their photothermal conversion mechanisms and the factors influencing their performance as well as their applications, including photo controlled ignition/deflagration, photothermal induced actuators, photo controlled metal processing, and concentrated sunlight energy conversion were elaborated.
View Article and Find Full Text PDFAdv Sci (Weinh)
September 2025
School of Mechanical & Automotive Engineering, South China University of Technology, Guangzhou, 510641, China.
Recently, flexible airflow sensors have attracted significant attention due to their impressive characteristics and capabilities for airflow sensing. However, the development of high-performance flexible airflow sensors capable of sensing airflow over large areas remains a challenge. In this work, it is proposed that a hair-like flexible airflow sensor, based on laser direct writing and electrostatic flocking, offers an efficient technology for airflow sensing.
View Article and Find Full Text PDFPhotoacoustics
October 2025
Hubei Key Laboratory of Intelligent Wireless Communications, Hubei Engineering Research Center of Intelligent IOT technology, College of Electronics and Information Engineering, South-Central Minzu University, Wuhan 430074, China.
A novel gourd-type photoacoustic cell (GTPAC) has been developed, featuring a highly reflective, polished gold film-coated inner wall that minimizes optical loss and maximizes light utilization efficiency. GTPAC integrates two coupled spherical chambers with a radius ratio 2:3, which is close to the golden ratio. Its unique Gaussian curvature distribution enables multi-directional, disordered light beam reflection without complex optical alignment.
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