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oe1(光电查) - 科学论文

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出版时间
  • 2019
  • 2018
  • 2017
  • 2016
研究主题
  • Optical pattern
  • Phase diagram
  • Surfactants
  • Optical properties
  • TB-MBJ
  • FP-LAPW
  • Electronic structure
  • GGA
  • DFT
  • Infrared Radiation
应用领域
  • Optoelectronic Information Science and Engineering
  • Chemistry
  • Materials Science and Engineering
机构单位
  • University of Texas at Arlington
  • Macquarie University
  • Universiti Malaysia Terengganu
  • Devi Ahilya University
  • National Institute of Information and Communications Technologies (NICT)
  • Povolzhskiy State University of Telecommunications and Informatics (PSUTI)
  • University of Sa?da Dr Tahar Moulay
  • University of Djillali Liabes
  • Assumption University
  • National Institute of Advanced Industrial Science and Technology
4497 条数据
?? 中文（中国） ▾

  • Dynamic regulating of single-mode lasing in ZnO microcavity by piezoelectric effect

    摘要： Realizing single-mode-lasing output while being able to dynamically select and regulate a specified resonant mode could bring revolutionary impact for laser technology, on-chip data communication, and optical sensing/switches. Here, we demonstrate a single-mode lasing achieved by the piezoresistive and piezoelectric polarization synergistic effect on an epoxy-encapsulated ZnO microresonator. Based on relative shifts of gain spectrum and the resonant wavelength, the lasing mode in a hexagonal ZnO rod can be selected and regulated dynamically within a certain range. The relationship between the corresponding applied strain and the tunable refractive index is analyzed in depth and discussed systematically. Our studies open up exciting avenues for constructing optical mode-phase modulator, high-sensitive optical switches and color-perceived optical sensing.

    关键词： optical sensing,ZnO microresonator,single-mode lasing,piezoelectric effect,dynamic regulation

    更新于2025-09-04 15:30:14

  • A Study on the Weak Ferromagnetism of Nanocrystalline Stannous Oxide Induced by L-Shaped O-Sn-O Vacancies

    摘要： Nanocrystalline stannous oxide (SnO) powder has been prepared by ball-milling of micron-SnO in a nitrogen atmosphere. A cation deficiency of 6.5% was found in the nano-SnO sample by X-ray photoelectron spectroscopy. After annealing at 350, 450, or 550℃ under dynamic vacuum conditions, oxygen vacancies were found in the nano-SnO samples, as verified by electron paramagnetic resonance experiments. The samples displayed weak ferromagnetism; that with both 6.5% Sn and at least 7.5% O vacancies showed the maximum saturation magnetization, reaching almost 1.7×10?3 emu/g at room temperature. The O vacancies tended to gather around Sn vacancies. An L-shaped defect model composed of one Sn and two O vacancies has been established, and its ferromagnetism has been calculated by a first-principles method. We found that the L-shaped defect induced a magnetic moment of 0.55 μB in the SnO lattice, the main contribution to which came from a spin-polarized electron in the p orbital of a corner Sn atom.

    关键词： Magnetic,Nanocrystalline Stannous Oxide,Plasmonics,L-Shaped O-Sn-O Vacancies,Weak Ferromagnetism,Optical,Hybrid Materials

    更新于2025-09-04 15:30:14

  • Tunable Goos–H?nchen and Imbert–Fedorov shifts

    摘要： The optical beam shift is a spatial displacement of an optical beam in geometrical optics that particularly occurs when a laser beam reflects from an interface. In this paper, the dependence of the Goos–H?nchen (GH) and Imbert–Fedorov (IF) shifts from the interface of quartz and garnet on the external direct current voltage (EDCV) are investigated by a Thorlabs BP209-IR slit beam profiler. The optical properties of the circularly polarized and linearly polarized laser beams are measured using a Thorlabs PAX 5710IR3 polarimeters. The results show that the change trend of the GH and IF shifts are the same, whereas the initial and terminal voltages are different. The maximum value of the GH and IF shifts are 20.9 μm and 33.4 μm when the EDCVs are at about 3.2 V and 2.0 V, respectively.

    关键词： Direct current,Optical beam shift,Polarization

    更新于2025-09-04 15:30:14

  • A two-year study of diffused retinal pigment epitheliopathy treated with half-dose photodynamic therapy guided by simultaneous angiography and optical coherence tomography

    摘要： Objectives Diffused retinal pigment epitheliopathy (DRPE) is not necessarily the same as chronic central serous chorioretinopathy (CSC), but a severe subgroup under the umbrella of chronic CSC. This study was to evaluate the efficacy and safety of half-dose PDT treating DRPE. Methods A retrospective case series design was used. Forty-eight consecutive patients (48 eyes) with DRPE treated with half-dose PDT underwent follow-up at baseline, 3 months, 6 months, 12 months and 24 months. Simultaneous FA, ICGA and OCT were used for the treatment and follow-up. The primary outcomes were the subretinal fluid and best-corrected visual acuity in optical coherence tomography. Results Complete fluid absorption was achieved in 95.8% of eyes at 3 months and 100.0% of eyes at 24 months. The baseline logarithm of the minimum angle of resolution (logMAR) BCVA, which was 0.51 ± 0.36, significantly improved to 0.43 ± 0.38 (p < 0.001) at 6 months. The boost continued to 0.29 ± 0.37 (p < 0.001) at 12 months and 0.19 ± 0.39 (p < 0.001) at 24 months. The integrities of the ellipsoid zone (EZ) and interdigitation zone (IZ) improved throughout. Regression analyses showed the BCVA in logMAR was inversely correlated with the EZ (p < 0.01) and IZ (p < 0.01). The recurrence rate was 6.3%. No severe complications were witnessed. Conclusions In 48 eyes with DRPE, simultaneous angiography and OCT facilitated a more comprehensive guidance for half-dose PDT treatment and follow-up. The BCVA improvement occurred at 6 months, which may be attributed to the restoration of the outer retinal structure.

    关键词： chronic central serous chorioretinopathy,half-dose photodynamic therapy,Diffused retinal pigment epitheliopathy,angiography,CSC,optical coherence tomography,OCT,DRPE,PDT

    更新于2025-09-04 15:30:14

  • Life sensors: current advances in oxygen sensing by lanthanide complexes

    摘要： Aerobes, such as animals, plants, fungi, and several bacteria, depend upon oxygen to live. Consequently, oxygen sensing comprises an emerging technique in many research fields, ranging from medicine to marine science. In the last few years, lanthanide-based oxygen sensors have seen significant progress in the field of optical sensing technology owing to their long luminescence lifetimes and sharp luminescence bands. These sensors provide an alternative to expensive transition metal-based sensors, such as platinum and ruthenium complexes. This review covers the development and design of lanthanide-based oxygen sensors, along with their photophysical properties related to oxygen sensing. These lanthanide complexes achieve oxygen sensing through the excited state quenching of the intermediate triplet state of the antenna chromophore, which suggests that the sensitivity to pO2 arises from the rate of forward intramolecular energy transfer from the antenna triplet state to the accepting Ln3+ ion being competitive with bimolecular quenching by oxygen. As Tb(III) complexes are highly oxygen sensitive, they are favored to be good oxygen sensors, while the sensitivity of Eu(III), Dy(III), Nd(III), and Gd(III) complexes is low.

    关键词： oxygen sensing,lanthanide complexes,Tb(III) complexes,optical sensing technology,photophysical properties

    更新于2025-09-04 15:30:14

  • Nanoapertures without nanolithography

    摘要： We propose and experimentally demonstrate the implementation of lithography-free nano-apertures on optical fibers. By sputtering metallic nanofilms onto the end face of step index fibers that contain central nano-channels, fiber-integrated nano-apertures are instantaneously implemented without the use of any kind of lithographic step. In accordance with simulations, the experiments show diffraction-limited nano-spots in the far-field at the location of the nano-aperture for sufficiently thick films. We reproducibly implement a series of devices by sputtering Al and Pt nano-films, reaching aperture diameters as small as 40 nm and showing spectrally broadband operation. Due to its simplicity, scalability and potential for large-scale production the nano-aperture enhanced fiber concept will be highly relevant for lab-on-a-fiber applications and for the development of future fiber-based nano-probes with high spatial resolutions.

    关键词： lab-on-a-fiber,hybrid fibers,nanofabrication,scanning near-field optical microscopy (SNOM),nanoapertures

    更新于2025-09-04 15:30:14

  • Optimal tone detection for optical fibre vector hydrophone

    摘要： An optimal tone detector based on the Neyman–Pearson criterion is proposed for the optical fibre vector hydrophone (OFVH). The detector takes account of the difference between noise levels on the acoustic pressure channel and the three particle acceleration channels of an OFVH. Explicit expressions for the impulse responses of pre-filters that are central to the proposed detector are given. Analyses show that the proposed detector is equivalent to the minimum variance distortionless response beamformer for the OFVH. In the case of identical noise on all particle acceleration channels, the signal-to-noise ratio (SNR) gain of the detector is 10lg(1 + μ) dB (μ is the noise power ratio of OFVH channels at the tone frequency), whereas the SNR gain also depends on target direction and is bounded by 10lg(1 + μmin) and 10lg(1 + μmax) dB when noise on all particle acceleration channels are different. Results from both simulations and lake experiment data show that the proposed detector outperforms tone detectors that use (i) the acoustic pressure signal, (ii) the particle acceleration signals and (iii) equally the combination of acoustic pressure signal and particle acceleration signals.

    关键词： signal-to-noise ratio gain,Neyman–Pearson criterion,optimal tone detector,optical fibre vector hydrophone

    更新于2025-09-04 15:30:14

  • A versatile dual-species Zeeman slower for caesium and ytterbium

    摘要： We describe the design, construction, and operation of a versatile dual-species Zeeman slower for both Cs and Yb, which is easily adaptable for use with other alkali metals and alkaline earths. With the aid of analytic models and numerical simulation of decelerator action, we highlight several real-world problems affecting the performance of a slower and discuss effective solutions. To capture Yb into a magneto-optical trap (MOT), we use the broad 1S0 to 1P1 transition at 399 nm for the slower and the narrow 1S0 to 3P1 intercombination line at 556 nm for the MOT. The Cs MOT and slower both use the D2 line (62S1/2 to 62P3/2) at 852 nm. The slower can be switched between loading Yb or Cs in under 0.1 s. We demonstrate that within a few seconds the Zeeman slower loads more than 109 Yb atoms and 108 Cs atoms into their respective MOTs. These are ideal starting numbers for further experiments on ultracold mixtures and molecules.

    关键词： caesium,Zeeman slower,dual-species,ytterbium,ultracold atoms,magneto-optical trap

    更新于2025-09-04 15:30:14

  • Standard quantum limit of sensitivity of an optical gyroscope

    摘要： We ?nd that the measurement sensitivity of an optical integrating gyroscope is fundamentally limited due to ponderomotive action of the light leading to the standard quantum limit of the rotation angle detection. The uncorrelated quantum ?uctuations of power of clockwise and counterclockwise electromagnetic waves result in optical power-dependent uncertainty of the angular gyroscope position. We also show that, on the other hand, a quantum backaction evading measurement of the angular momentum of a gyroscope becomes feasible if the proper measurement strategy is selected. The angle is perturbed in this case. This observation hints at the fundamental inequivalence of integrating and rate gyroscopes.

    关键词： optical gyroscope,quantum limit,quantum backaction,rate gyroscope,integrating gyroscope,ponderomotive action

    更新于2025-09-04 15:30:14

  • [IEEE 2018 Iranian Conference on Electrical Engineering (ICEE) - Mashhad (2018.5.8-2018.5.10)] Electrical Engineering (ICEE), Iranian Conference on - Tunable Filter by Using Parity Time (PT) Symmetric Periodic Array Electronic

    摘要： A circuit model of a periodic array of PT-symmetric (gain/loss coupled) waveguides is reported for the design of a novel tunable filter. This model consists of a pair of coupled circuits, one with amplification resistance and the other with an equivalent attenuation. By varying the value of the gain/loss, one can control the size of bandgap and hence the allowed frequencies propagating within the structure. For a critical value of gain/loss, the eigenvalues merge and the gap disappears. As a result, all frequencies can pass the structure i.e, an all pass filter. The Q-factor of reflected frequency can be varied such that, tunable Q from 20 to greatest has been successfully realized in the central frequency of 0.283 MHz. The remarkable feature of this design lies with its tunability, high speed, and relative simplicity.

    关键词： RLC Circuit Model,Parity-Time (PT) Symmetry,Grating Waveguides,Optical Waveguides,Band Stop Filter (BSF)

    更新于2025-09-04 15:30:14