This Letter presents intrinsic Fabry–Perot interferometers in the fiber tapers fabricated by the femtosecond laser micromachining technique. The sensing of temperatures as high as 1000°C based on the fiber devic...This Letter presents intrinsic Fabry–Perot interferometers in the fiber tapers fabricated by the femtosecond laser micromachining technique. The sensing of temperatures as high as 1000°C based on the fiber device is characterized, with a sensitivity of 15.28 pm∕°C. A nearly linear refractive index sensing is also obtained by using the fringe visibility to characterize, with a sensitivity of 73.05 dB∕RIU. These intrinsic Fabry–Perot interferometers in fiber tapers may be useful in applications of high-temperature and linear refractive index sensing.展开更多
Fabry–Perot(FP)modes are a class of fundamental resonances in photonic crystal(PhC)slabs.Owing to their low quality factors,FP modes are frequently considered as background fields with their resonance nature being ne...Fabry–Perot(FP)modes are a class of fundamental resonances in photonic crystal(PhC)slabs.Owing to their low quality factors,FP modes are frequently considered as background fields with their resonance nature being neglected.Nevertheless,FP modes can play important roles in some phenomena,as exemplified by their coupling with guided resonance(GR)modes to achieve bound states in the continuum(BIC).Here,we further demonstrate the genuine resonance mode capability of FP modes PhC slabs.Firstly,we utilize temporal coupled-mode theory to obtain the transmittance of a PhC slab based on the FP modes.Secondly,we construct exceptional points(EPs)in both momentum and parameter spaces through the coupling of FP and GR modes.Furthermore,we identify a Fermi arc connecting two EPs and discuss the far-field polarization topology.This work elucidates that the widespread FPs in PhC slabs can serve as genuine resonant modes,facilitating the realization of desired functionalities through mode coupling.展开更多
A scanning Fabry–Perot interferometer(SFPI)was first developed and deployed at the Langfang near Space Environment Field Scientific Observation Station(39.38°N,116.65°E)of the National Space Science Center,...A scanning Fabry–Perot interferometer(SFPI)was first developed and deployed at the Langfang near Space Environment Field Scientific Observation Station(39.38°N,116.65°E)of the National Space Science Center,CAS.The instrument is designed to measure the mesospheric and thermospheric wind velocities using the atomic oxygen 557.7-nm and 630.0-nm emissions.Data from February 28 to March 3and February 28 to March 15 in 2011 were chosen for case study and mean value study,respectively.The errors of the meridional and zonal winds are 6.5 and 7.5 m/s at 557.7-nm and at 630.0-nm,they are 7.1 and 6.6 m/s,respectively.During the whole experiment,the instrument has performed in good condition and provided high-quality data.The mean neutral wind data were consistent with that predicted by HWM07.Good agreement has been found in between the SFPI and a neighbor Meridian Project Fabry–Perot interferometer(MP FPI),with a corresponding coefficient(r2)larger than 80%.In general,the scanning FPI meets the design goal,and it is a useful ground-based instrument for measuring mesospheric and thermospheric winds at middle latitudes and is able to provide high-quality data for future scientific studies.展开更多
An ultrasonic sensitivity-improved fiber-optic Fabry-Perot interferometer （FPI） is proposed and employed for ultra- sonic imaging of seismic physical models （SPMs）. The FPI comprises a flexible ultra-thin gold fil...An ultrasonic sensitivity-improved fiber-optic Fabry-Perot interferometer （FPI） is proposed and employed for ultra- sonic imaging of seismic physical models （SPMs）. The FPI comprises a flexible ultra-thin gold film and the end face of a graded-index multimode fiber （MMF）, both of which are enclosed in a ceramic tube. The MMF in a specified length can collimate the diverged light beam and compensate for the light loss inside the air cavity, leading to an increased spectral fringe visibility and thus a steeper spectral slope. By using the spectral sideband filtering technique, the collimated FP1 shows an improved ultrasonic response. Moreover, two-dimensional images of two SPMs are achieved in air by recon- structing the pulse-echo signals through using the time-of-flight approach. The proposed sensor with easy fabrication and compact size can be a good candidate for high-sensitivity and high-precision nondestructive testing of SPMs.展开更多
A simple capillary-based extrinsic Fabry–Perot structure is presented and fabricated, using the manual welding method with the strain sensing characteristics investigated in detail. Strain sensitivities of 4.2, 2.8, ...A simple capillary-based extrinsic Fabry–Perot structure is presented and fabricated, using the manual welding method with the strain sensing characteristics investigated in detail. Strain sensitivities of 4.2, 2.8, and2.4 pm∕με are obtained experimentally with the interferometer length around 50 μm and the inner diameter of 75, 50, and 25 μm, respectively. The underlying physics of the strain sensitivity of this device is negatively correlated with the interferometer length and positively correlated with the capillary inner diameter, which provides two simple parameters to tailor the strain sensitivity.展开更多
An optical fiber extrinsic Fabry-Perot interferometer （EFPI） is designed and fabricated for refractive index （RI） sensing. To test the RI of liquid, the following two different methods are adopted： the wavelength...An optical fiber extrinsic Fabry-Perot interferometer （EFPI） is designed and fabricated for refractive index （RI） sensing. To test the RI of liquid, the following two different methods are adopted： the wavelength tracking method and the Fourier-transform white-light interferometry （FTWLI）. The sensitivities of sensors with cavity lengths of 288.1 and 358.5 μm are 702.312 nm/RIU and 396.362 μm/RIU, respectively, by the two methods. Our work provides a new kind of RI sensor with the advantages of high sensitivity, mechanical robustness, and low cross sensitivity to temperature. Also, we provide a new method to deal with gold film with a femtosecond laser.展开更多
This paper presents a novel miniaturized fiber-optic Fabry-Peort interferometer （FPI） for highly sensitive refractive index measurement. This device was tested for the refractive indices of various liquids including...This paper presents a novel miniaturized fiber-optic Fabry-Peort interferometer （FPI） for highly sensitive refractive index measurement. This device was tested for the refractive indices of various liquids including acetone and ethanol at room temperature. The sensitivity for measurement of refractive index change of ethanol is 1138 nm/RIU at the wavelength of 1550 nm. In addition, the sensor fabrication is simple including only cleaving, splicing, and etching. The signal is stable with high visibility. Therefore, it provides a valuable tool in biological and chemical applications.展开更多
The electronic Fabry–Pérot interferometer operating in the quantum Hall regime may be a promising tool for probing edge state interferences and studying the non-Abelian statistics of fractionally charged quasipa...The electronic Fabry–Pérot interferometer operating in the quantum Hall regime may be a promising tool for probing edge state interferences and studying the non-Abelian statistics of fractionally charged quasiparticles. Here we report on realizing a quantum Hall Fabry–Pérot interferometer based on monolayer graphene. We observe resistance oscillations as a function of perpendicular magnetic field and gate voltage both on the electron and hole sides. Their Coulomb-dominated origin is revealed by the positive(negative) slope of the constant phase lines in the plane of magnetic field and gate voltage on the electron(hole) side. Our work demonstrates that the graphene interferometer is feasible and paves the way for the studies of edge state interferences since high-Landau-level and even denominator fractional quantum Hall states have been found in graphene.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61377081 and 61007035)the Chen Guang project by Shanghai Municipal Education Commission and Shanghai Education Development Foundation(No.12CG48)the Science and Technology Commission of Shanghai Municipality(STCSM)(No.14511105602)
文摘This Letter presents intrinsic Fabry–Perot interferometers in the fiber tapers fabricated by the femtosecond laser micromachining technique. The sensing of temperatures as high as 1000°C based on the fiber device is characterized, with a sensitivity of 15.28 pm∕°C. A nearly linear refractive index sensing is also obtained by using the fringe visibility to characterize, with a sensitivity of 73.05 dB∕RIU. These intrinsic Fabry–Perot interferometers in fiber tapers may be useful in applications of high-temperature and linear refractive index sensing.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.12074049 and 12347101)。
文摘Fabry–Perot(FP)modes are a class of fundamental resonances in photonic crystal(PhC)slabs.Owing to their low quality factors,FP modes are frequently considered as background fields with their resonance nature being neglected.Nevertheless,FP modes can play important roles in some phenomena,as exemplified by their coupling with guided resonance(GR)modes to achieve bound states in the continuum(BIC).Here,we further demonstrate the genuine resonance mode capability of FP modes PhC slabs.Firstly,we utilize temporal coupled-mode theory to obtain the transmittance of a PhC slab based on the FP modes.Secondly,we construct exceptional points(EPs)in both momentum and parameter spaces through the coupling of FP and GR modes.Furthermore,we identify a Fermi arc connecting two EPs and discuss the far-field polarization topology.This work elucidates that the widespread FPs in PhC slabs can serve as genuine resonant modes,facilitating the realization of desired functionalities through mode coupling.
基金supported by the National Hightech R&D Program of China(2008AA7033050,2009AA7033050,and 2010AA7033050)
文摘A scanning Fabry–Perot interferometer(SFPI)was first developed and deployed at the Langfang near Space Environment Field Scientific Observation Station(39.38°N,116.65°E)of the National Space Science Center,CAS.The instrument is designed to measure the mesospheric and thermospheric wind velocities using the atomic oxygen 557.7-nm and 630.0-nm emissions.Data from February 28 to March 3and February 28 to March 15 in 2011 were chosen for case study and mean value study,respectively.The errors of the meridional and zonal winds are 6.5 and 7.5 m/s at 557.7-nm and at 630.0-nm,they are 7.1 and 6.6 m/s,respectively.During the whole experiment,the instrument has performed in good condition and provided high-quality data.The mean neutral wind data were consistent with that predicted by HWM07.Good agreement has been found in between the SFPI and a neighbor Meridian Project Fabry–Perot interferometer(MP FPI),with a corresponding coefficient(r2)larger than 80%.In general,the scanning FPI meets the design goal,and it is a useful ground-based instrument for measuring mesospheric and thermospheric winds at middle latitudes and is able to provide high-quality data for future scientific studies.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61735014,61327012,and 61275088)the Scientific Research Program Funded by Shaanxi Provincial Education Department,China(Grant No.08JZ58)the Northwest University Graduate Innovation and Creativity Funds,China(Grant No.YZZ17088)
文摘An ultrasonic sensitivity-improved fiber-optic Fabry-Perot interferometer （FPI） is proposed and employed for ultra- sonic imaging of seismic physical models （SPMs）. The FPI comprises a flexible ultra-thin gold film and the end face of a graded-index multimode fiber （MMF）, both of which are enclosed in a ceramic tube. The MMF in a specified length can collimate the diverged light beam and compensate for the light loss inside the air cavity, leading to an increased spectral fringe visibility and thus a steeper spectral slope. By using the spectral sideband filtering technique, the collimated FP1 shows an improved ultrasonic response. Moreover, two-dimensional images of two SPMs are achieved in air by recon- structing the pulse-echo signals through using the time-of-flight approach. The proposed sensor with easy fabrication and compact size can be a good candidate for high-sensitivity and high-precision nondestructive testing of SPMs.
基金supported by the National Natural Science Foundation of China(Nos.61675126,61377081,and61007035)the Chen Guang Project by the Shanghai Municipal Education Commission and Shanghai Education Development Foundation(No.12CG48)
文摘A simple capillary-based extrinsic Fabry–Perot structure is presented and fabricated, using the manual welding method with the strain sensing characteristics investigated in detail. Strain sensitivities of 4.2, 2.8, and2.4 pm∕με are obtained experimentally with the interferometer length around 50 μm and the inner diameter of 75, 50, and 25 μm, respectively. The underlying physics of the strain sensitivity of this device is negatively correlated with the interferometer length and positively correlated with the capillary inner diameter, which provides two simple parameters to tailor the strain sensitivity.
基金supported by the National Basic Research Program of China (No.2011CB013000)the 863 Program of the Ministry of Science and Technology of China (No.2015AA043504)the Cultivation Fund of the Key Scientific and Technical Innovation Project,Ministry of Education of China (No.708018)
文摘An optical fiber extrinsic Fabry-Perot interferometer （EFPI） is designed and fabricated for refractive index （RI） sensing. To test the RI of liquid, the following two different methods are adopted： the wavelength tracking method and the Fourier-transform white-light interferometry （FTWLI）. The sensitivities of sensors with cavity lengths of 288.1 and 358.5 μm are 702.312 nm/RIU and 396.362 μm/RIU, respectively, by the two methods. Our work provides a new kind of RI sensor with the advantages of high sensitivity, mechanical robustness, and low cross sensitivity to temperature. Also, we provide a new method to deal with gold film with a femtosecond laser.
基金supported by the Key Project of Natural Science Foundation of China under Grant No. 60537040the Natural Science Foundation Project of CQ CSTC under Grant No. 2007BB3125
文摘This paper presents a novel miniaturized fiber-optic Fabry-Peort interferometer （FPI） for highly sensitive refractive index measurement. This device was tested for the refractive indices of various liquids including acetone and ethanol at room temperature. The sensitivity for measurement of refractive index change of ethanol is 1138 nm/RIU at the wavelength of 1550 nm. In addition, the sensor fabrication is simple including only cleaving, splicing, and etching. The signal is stable with high visibility. Therefore, it provides a valuable tool in biological and chemical applications.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2016YFA0300601 and 2017YFA0303304)the National Natural Science Foundation of China(Grant Nos.11874071,11774005,and 11974026)Beijing Academy of Quantum Information Sciences,China(Grant No.Y18G22)
文摘The electronic Fabry–Pérot interferometer operating in the quantum Hall regime may be a promising tool for probing edge state interferences and studying the non-Abelian statistics of fractionally charged quasiparticles. Here we report on realizing a quantum Hall Fabry–Pérot interferometer based on monolayer graphene. We observe resistance oscillations as a function of perpendicular magnetic field and gate voltage both on the electron and hole sides. Their Coulomb-dominated origin is revealed by the positive(negative) slope of the constant phase lines in the plane of magnetic field and gate voltage on the electron(hole) side. Our work demonstrates that the graphene interferometer is feasible and paves the way for the studies of edge state interferences since high-Landau-level and even denominator fractional quantum Hall states have been found in graphene.
