- 标题
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[IEEE 2019 IEEE Photonics Conference (IPC) - San Antonio, TX, USA (2019.9.29-2019.10.3)] 2019 IEEE Photonics Conference (IPC) - Frequency Noise Reduction of Quantum Cascade Lasers using Optical Feedback
摘要： We theoretically demonstrate that strong optical feedback can reduce the frequency noise of quantum cascade lasers by two orders of magnitude, which is almost independent on the feedback phase. In addition, the spectral linewidth of the laser with optical feedback is analytically derived.
关键词： frequency noise,quantum cascade laser,optical feedback,spectral linewidth
更新于2025-09-11 14:15:04
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Photonic Microcavity-Enhanced Magnetic Plasmon Resonance of Metamaterials for Sensing Applications
摘要： We investigate photonic microcavity-enhanced magnetic plasmon (MP) resonance in metamaterials for high-quality refractive index sensing. The metamaterials are consisting of a top periodic array of U-shaped metallic split-ring resonators (SRRs), a middle dielectric layer, and a bottom metallic backed plate. The top metallic SRRs that are placed at about Bragg distance above the bottom metallic plate constitute a photonic microcavity. Because the MP resonance excited in metallic SRRs is coupled to the photonic microcavity mode supported by the photonic microcavity, the radiative damping of the MP resonance is strongly reduced and consequently its linewidth is decreased dramatically. Benefiting from the narrow linewidth, large modulation depth, and giant magnetic field enhancement at the MP resonance, the cavity-coupled metamaterial sensor has very high sensitivity (S =400 nm/RIU, S* =26/RIU) and figure of merit (FOM =33, FOM* =4215), which suggests that the proposed metamaterials have potential in applications of plasmonic biosensors.
关键词： Optical sensing and sensors,Narrow linewidth,Magnetic field enhancement,Photonic microcavity,Metamaterials
更新于2025-09-10 09:29:36
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Linewidth calibration using a metrological atomic force microscope with a tip-tilting mechanism
摘要： The linewidth or critical dimension (CD) of a nanoscale line pattern is calibrated using a metrological atomic force microscope with a tip-tilting mechanism (tilting-mAFM). The tilting tip allows scanning of the line pattern’s vertical sidewalls. The tilting-mAFM performs two measurements on each side of the line pattern, and two datasets are stitched together to reconstruct the complete shape of the line pattern. Further, CD is measured based on this pattern. A linewidth standard with a subnanometer-scale uncertainty was used as a target sample to verify this CD calibration procedure. The calibrated CD using tilting-mAFM was 111.2 nm with an expanded uncertainty of 1.0 nm, which was the smallest uncertainty that was observed among the CD measurements that were reported using the tilting-AFM instruments. Further, the difference of this CD value from the reference CD was only 0.2 nm. The results reveal that tilting-mAFM can be used for CD metrology with a single-nanometer accuracy.
关键词： metrological AFM,critical dimension (CD),calibration,tilting-AFM,nanometrology,linewidth
更新于2025-09-10 09:29:36
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High power all-fiberized and narrow-bandwidth MOPA system by tandem pumping strategy for thermally induced mode instability suppression
摘要： An all-?berized and narrow-bandwidth master oscillator power ampli?cation (MOPA) system with record output power of 4 kW level and slope ef?ciency of 78% is demonstrated. Tandem pumping strategy is tentatively introduced into the narrow-bandwidth MOPA system for thermally induced mode instability (TMI) suppression. The stimulated Brillouin scattering (SBS) effect is balanced by simply using one-stage phase modulation technique. With different phase modulation signals, SBS limited output powers of 336 W, 1.2 kW and 3.94 kW are respectively achieved with spectral bandwidths accounting for 90% power of ～0.025, 0.17 and ～0.89 nm. Compared with our previous 976 nm pumping system, TMI threshold is overall boosted to be >5 times in which tandem pumping increases the TMI threshold of >3 times. The beam quality (M 2 factor) of the output laser is well within 1.5 below the TMI threshold while it is ultimately saturated to be 1.86 with the in?uence of TMI at maximal output power. Except for SBS and TMI, stimulated Raman scattering (SRS) effect will be another challenge for further power scaling. In such a high power MOPA system, multi-detrimental effects (SBS, SRS and TMI) will coexist and may be mutual-coupled, which could provide a well platform for further comprehensively investigating and optimizing the high power, narrow-bandwidth ?ber ampli?ers.
关键词： optimization,design,laser ampli?ers,narrow linewidth,high power laser,laser systems,modeling,advanced laser technology and applications,?ber laser and applications
更新于2025-09-10 09:29:36
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Transverse relaxation determination based on light polarization modulation for spin-exchange relaxation free atomic magnetometer
摘要： A transverse relaxation determination of spin-exchange relaxation free (SERF) magnetometer based on polarization modulation technique is proposed. Compared with the radio-frequency (RF) excitation and light intensity excitation methods used in SERF magnetometer, the light polarization modulation method has a high stability in low-frequency range, which indicates a more accurate transverse relaxation measurement.
关键词： linewidth,spin-exchange relaxation free (SERF) magnetometer,optical polarization modulation
更新于2025-09-09 09:28:46