Control and detection of antiferromagnetic topological materials are challenging since the total magnetization vanishes.Here we investigate the magneto-optical Kerr and Faraday effects in bilayer antiferromagnetic ins...Control and detection of antiferromagnetic topological materials are challenging since the total magnetization vanishes.Here we investigate the magneto-optical Kerr and Faraday effects in bilayer antiferromagnetic insulator Mn Bi2Te4.We find that by breaking the combined mirror symmetries with either perpendicular electric field or external magnetic moment,Kerr and Faraday effects occur.Under perpendicular electric field,antiferromagnetic topological insulators(AFMTI)show sharp peaks at the interband transition threshold,whereas trivial insulators show small adjacent positive and negative peaks.Gate voltage and Fermi energy can be tuned to reveal the differences between AFMTI and trivial insulators.We find that AFMTI with large antiferromagnetic order can be proposed as a pure magneto-optical rotator due to sizable Kerr(Faraday)angles and vanishing ellipticity.Under external magnetic moment,AFMTI and trivial insulators are significantly different in the magnitude of Kerr and Faraday angles and ellipticity.For the qualitative behaviors,AFMTI shows distinct features of Kerr and Faraday angles when the spin configurations of the system change.These phenomena provide new possibilities to optically detect and manipulate the layered topological antiferromagnets.展开更多
We demonstrate an 852-nm external cavity diode laser(ECDL) system whose wavelength is mainly determined by an interference filter instead of other wavelength selective elements. The Lorentzian linewidth measured by ...We demonstrate an 852-nm external cavity diode laser(ECDL) system whose wavelength is mainly determined by an interference filter instead of other wavelength selective elements. The Lorentzian linewidth measured by the heterodyne beating between two identical lasers is 28.3 k Hz. Moreover, we test the application of the ECDL in the Faraday atomic filter.Besides saturated absorption spectrum, the transmission spectrum of the Faraday atomic filter at 852 nm is measured by using the ECDL. This interference filter ECDL method can also be extended to other wavelengths and widen the application range of diode laser.展开更多
A narrow linewidth Faraday anomalous dispersion optical filter(FADOF)with reflection configuration is achieved for the first time based on the cesium(Cs)ground state 6S_(1/2) to the excited state 6P_(3/2) transition a...A narrow linewidth Faraday anomalous dispersion optical filter(FADOF)with reflection configuration is achieved for the first time based on the cesium(Cs)ground state 6S_(1/2) to the excited state 6P_(3/2) transition at 852 nm.Compared with the conventional FADOF with transmission configuration,reflection-type FADOF can greatly improve the transmittance of optical filter under the same experimental parameters,because it allows signal light to go and return through the atomic vapor cell.In our experiment,peak transmittance at Cs 6S_(1/2) F=4-6P_(3/2) transition is 81%for the reflection-type FADOF,and while 54%for the transmission-type FADOF when the temperature of Cs vapor cell and the axial magnetic field are 60℃and 19 G.The idea of this reflection-type FADOF design has the potential to be applied to the FADOF operating between two excited states to obtain higher transmittance.展开更多
A method that obtains the Ramsey-coherent population trapping (CPT) spectrum with the Faraday effect is investi- gated. An experiment is implemented to detect the light polarization components generated from the Far...A method that obtains the Ramsey-coherent population trapping (CPT) spectrum with the Faraday effect is investi- gated. An experiment is implemented to detect the light polarization components generated from the Faraday effect. The experimental results agree with the theoretical calculations based on the Liouville equation. By comparing with the method without using the Faraday effect, the potential of this method for a CPT-based atomic clock is assessed. The results indicate that this method should improve the short-term frequency stability by several times.展开更多
Magneto-optic fiber Bragg gratings (MFBG) based on magneto-optic materials have a lot of potential applications for sensing and optical signal processing. The transmission and reflection spectra of guided optical wa...Magneto-optic fiber Bragg gratings (MFBG) based on magneto-optic materials have a lot of potential applications for sensing and optical signal processing. The transmission and reflection spectra of guided optical waves in the MFBG are investigated. According to the sensitivity of MFBG spectral lines to the magneto-optic coupling intensity varying with applied magnetic field, a novel magnetic field sensor of high-resolution up to 0.01 nm/(kA/m) is predicted.展开更多
We investigated in detail how photonic band structures (PBSs) of one dimensional plasma photonic crystals (PPCs) are tuned after being exposed to an external magnetic field. We showed that the properties of PBSs o...We investigated in detail how photonic band structures (PBSs) of one dimensional plasma photonic crystals (PPCs) are tuned after being exposed to an external magnetic field. We showed that the properties of PBSs of PPCs are tuned correspondingly because the dielectric constant of the micro plasma layer is modified differently in different frequency ranges due to magneto-optical effects. Two numerical cases are calculated and discussed to study the magneto-optical effects on the properties of PBSs, including the Faraday and Voigt effects.展开更多
A multichannel methanoic acid (HCOOH, λ=432.5 μm) laser interferometer/polarimeter is being developed from the previous eight-channel hydrogen cyanide (HCN, λ=337 μm) laser interferometer in the HL-2A tokamak....A multichannel methanoic acid (HCOOH, λ=432.5 μm) laser interferometer/polarimeter is being developed from the previous eight-channel hydrogen cyanide (HCN, λ=337 μm) laser interferometer in the HL-2A tokamak. A conventional Michelson-type interometer is used for the electron density measurement, and a Dodel-Kunz-type polarimeter is used for the Faraday rotation effect measurement, respectively. Each HCOOH laser can produce a linearly polarized radiation at a power lever of -30 mW, and a power stability 〈10% in 50 rain. A beam waist (diameter d0 ≈12.0 mm, about 200 mm away from the outlet) is finally determined through a chopping modulation technique. The latest optical layout of the interferometer/polarimeter has been finished, and the hardware data processing system based on the fast Fourier transform phase- comparator technique is being explored. In order to demonstrate the feasibility of the diagnostic scheme, two associated bench simulation experiments were carried out in the laboratory, in which the plasma was simulated by a piece of polytetrafluoroethene plate, and the Faraday rotation effect was simulated by a rotating half-wave plate. Simulation results agreed well with the initial experimental conditions. At present, the HCOOH laser interferometer/polarimeter system is being assembled on HL-2A, and is planned to be applied in the 2014-2015 experimental campaign.展开更多
A research on passive optical fiber current sensor based on magneto-optical crystal and a new design of light path of the sensor head are presented. Both methods of dual-channel optical detection of the polarization s...A research on passive optical fiber current sensor based on magneto-optical crystal and a new design of light path of the sensor head are presented. Both methods of dual-channel optical detection of the polarization state of the output light and signal processing are proposed. Signal processing can obtain the linear output of the current measurement of the wire more conveniently. Theoretical analysis on the magnetooptical fiber current sensor is given, followed by experiments. After that, further analysis is made according to the results, which leads to clarifying the exiting problems and their placements.展开更多
We demonstrate a high power,Er:Lu AG single-longitudinal-mode laser in an anti-misaligned resonator.Based on the Faraday effect,a 1.61 W single-longitudinal-mode(SLM)laser is obtained with the double corner-cube-retro...We demonstrate a high power,Er:Lu AG single-longitudinal-mode laser in an anti-misaligned resonator.Based on the Faraday effect,a 1.61 W single-longitudinal-mode(SLM)laser is obtained with the double corner-cube-retroreflector(CCR)structure,and the tunable wavelength is 1649.2-1650.3 nm.Additionally,we investigate the anti-misalignment characteristics when the CCR moves and rotates along the optical axis.Furthermore,by utilizing the Er:Lu AG amplifier,the maximum 2.32 W single-longitudinal-mode laser at 1649.6 nm is achieved.The beam quality factors M^(2) of the 2.32 W Er:Lu AG single-longitudinal-mode laser are 1.23 and 1.25 along the horizontal(x)and vertical(y)directions,respectively.展开更多
An ultranarrow bandwidth Faraday atomic filter is realized based on cold 87Rb atoms. The atomic filter operates at 780 nm on the 52 S1/2, F = 2 to 52 P3/2, F’= 3 transition with a bandwidth of 7.1(8) MHz, which is ap...An ultranarrow bandwidth Faraday atomic filter is realized based on cold 87Rb atoms. The atomic filter operates at 780 nm on the 52 S1/2, F = 2 to 52 P3/2, F’= 3 transition with a bandwidth of 7.1(8) MHz, which is approaching the natural linewidth of the transition. The peak transmission achieves 2.6(3)% by the multi-pass probe method. This atomic filter based on cold atoms may find potential applications in self-stabilizing lasers in the future.展开更多
Faraday effect measurements of holmium oxide(Ho_2O_3) ceramics-based magneto-optical materials, highly potential material candidates for high-energy laser Faraday isolators, are presented in this paper. Temperature de...Faraday effect measurements of holmium oxide(Ho_2O_3) ceramics-based magneto-optical materials, highly potential material candidates for high-energy laser Faraday isolators, are presented in this paper. Temperature dependence of the Verdet constant of nondoped Ho_2O_3 ceramics was measured for temperatures 15–305 K at 1.064 μm wavelength.The Verdet constant dispersion for wavelengths 0.5–1 μm and 1.064 μm was measured for both nondoped Ho_2O_3 ceramics and Ho_2O_3 ceramics doped with terbium Tb3+(0.2 at. %) and cerium Ce3+(0.1 at. %) ions. The results suggest that the relatively low level of doping of Ho_2O_3 with these ions has no significant boosting impact on the Faraday effect. Therefore, other compositions of Ho_2O_3 ceramics-based magneto-optical materials, as well as various doping concentrations, should be further examined.展开更多
Fiber quarter-wave plates and magneto-optical fibers are important components that greatly affect the sensitivity of fiberoptic current sensors.A Tb:YAG crystal-derived silica fiber(TYDSF)was fabricated using a CO_(2)...Fiber quarter-wave plates and magneto-optical fibers are important components that greatly affect the sensitivity of fiberoptic current sensors.A Tb:YAG crystal-derived silica fiber(TYDSF)was fabricated using a CO_(2) laser-heating drawing technique.The linear birefringence of TYDSF was measured as 6.661×10^(-6)by a microscope birefringence measurement instrument.A fiber quarter-wave plate was fabricated by TYDSF at 1310 nm,which produced circularly polarized light with a polarization extinction ratio of 0.34 d B.Additionally,the linear birefringence of TYDSF was decreased by 22%by annealing at 750℃ for 7 h,and the Verdet constants of annealed TYDSF were measured to be 9.83,6.67,and 3.48 rad/(T·m)at 808,980,and 1310 nm,respectively.展开更多
A novel fiber-optic current sensing scheme is proposed by converting the Faraday rotation to the optical signal's degree of polarization (DOP) change. In this scheme, the lightwave passes through a fiber resonant c...A novel fiber-optic current sensing scheme is proposed by converting the Faraday rotation to the optical signal's degree of polarization (DOP) change. In this scheme, the lightwave passes through a fiber resonant cavity multiply and experiences Faraday rotation simultaneously. Its main merit is immunity from the environment disturbance to the fiber used in ordinary Faraday rotation sensor. Brief theoretical analysis and simulation are given to show its basic characteristics. Experimental results are demonstrated and the feasibility of the proposed method is also shown.展开更多
We demonstrate an all-optical strategy for realizing spherical three-dimensional(3D)super-resolution(∼λ3/22)spot arrays of pure longitudinal magnetization by exploiting a 4πoptical microscopic setup with two high n...We demonstrate an all-optical strategy for realizing spherical three-dimensional(3D)super-resolution(∼λ3/22)spot arrays of pure longitudinal magnetization by exploiting a 4πoptical microscopic setup with two high numerical aperture(NA)objective lenses,which focus and interfere two modulated vectorial beams.Multiple phase filters(MPFs)are designed via an analytical approach derived from the vectorial Debye diffraction theory to modulate the two circularly polarized beams.The system is tailored to constructively interfere the longitudinal magnetization components,while simultaneously destructively interfering the azimuthal ones.As a result,the magnetization field is not only purely longitudinal but also super-resolved in all three dimensions.Furthermore,the MPFs can be designed analytically to control the number and locations of the super-resolved magnetization spots to produce both uniform and nonuniform arrays in a 3D volume.Thus,an all-optical control of all the properties of light-induced magnetization spot arrays has been demonstrated for the first time.These results open up broad applications in magnetic-optical devices such as confocal and multifocal magnetic resonance microscopy,3D ultrahigh-density magneto-optic memory,and light-induced magneto-lithography.展开更多
The dynamic performances of magneto-optical Bi-substituted rare-earth iron garnet (BIG) under different external magnetic fields and at different frequencies are experimentally studied. The measurement data indicate t...The dynamic performances of magneto-optical Bi-substituted rare-earth iron garnet (BIG) under different external magnetic fields and at different frequencies are experimentally studied. The measurement data indicate that the Faraday rotation angle is almost proportional to the external magnetic field when the garnet is far less saturated, while there is good switch performance when it is saturated. The higher the working frequency is, the larger the saturation magnetic field and the phase delay of Faraday angle relative to the field. The saturation fields and the phase delays at different frequencies are measured. The dynamic performance of the BIG determines the performance of BIG-based optical devices. To get the better performance of such devices, the garnets with small dampness and large stiffness should be chosen elaborately.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11904062)the Starting Research Fund from Guangzhou University(Grant No.RQ2020076)Guangzhou Basic Research Program,jointed funded by Guangzhou University(Grant No.202201020186)。
文摘Control and detection of antiferromagnetic topological materials are challenging since the total magnetization vanishes.Here we investigate the magneto-optical Kerr and Faraday effects in bilayer antiferromagnetic insulator Mn Bi2Te4.We find that by breaking the combined mirror symmetries with either perpendicular electric field or external magnetic moment,Kerr and Faraday effects occur.Under perpendicular electric field,antiferromagnetic topological insulators(AFMTI)show sharp peaks at the interband transition threshold,whereas trivial insulators show small adjacent positive and negative peaks.Gate voltage and Fermi energy can be tuned to reveal the differences between AFMTI and trivial insulators.We find that AFMTI with large antiferromagnetic order can be proposed as a pure magneto-optical rotator due to sizable Kerr(Faraday)angles and vanishing ellipticity.Under external magnetic moment,AFMTI and trivial insulators are significantly different in the magnitude of Kerr and Faraday angles and ellipticity.For the qualitative behaviors,AFMTI shows distinct features of Kerr and Faraday angles when the spin configurations of the system change.These phenomena provide new possibilities to optically detect and manipulate the layered topological antiferromagnets.
基金supported by the National Natural Science Foundation of China(Grant No.91436210)the International Science and Technology Cooperation Program of China(Grant No.2010DFR10900)
文摘We demonstrate an 852-nm external cavity diode laser(ECDL) system whose wavelength is mainly determined by an interference filter instead of other wavelength selective elements. The Lorentzian linewidth measured by the heterodyne beating between two identical lasers is 28.3 k Hz. Moreover, we test the application of the ECDL in the Faraday atomic filter.Besides saturated absorption spectrum, the transmission spectrum of the Faraday atomic filter at 852 nm is measured by using the ECDL. This interference filter ECDL method can also be extended to other wavelengths and widen the application range of diode laser.
基金the National Natural Science Foundation of China(Grant Nos.61975102 and 11974226)the National Key Research and Development Program of China(Grant No.2017YFA0304502)+1 种基金the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi,China(Grant No.2019L0101)the Natural Science Foundation of Shanxi Province,China(Grant No.20210302123437).
文摘A narrow linewidth Faraday anomalous dispersion optical filter(FADOF)with reflection configuration is achieved for the first time based on the cesium(Cs)ground state 6S_(1/2) to the excited state 6P_(3/2) transition at 852 nm.Compared with the conventional FADOF with transmission configuration,reflection-type FADOF can greatly improve the transmittance of optical filter under the same experimental parameters,because it allows signal light to go and return through the atomic vapor cell.In our experiment,peak transmittance at Cs 6S_(1/2) F=4-6P_(3/2) transition is 81%for the reflection-type FADOF,and while 54%for the transmission-type FADOF when the temperature of Cs vapor cell and the axial magnetic field are 60℃and 19 G.The idea of this reflection-type FADOF design has the potential to be applied to the FADOF operating between two excited states to obtain higher transmittance.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11304362 and 11204351)
文摘A method that obtains the Ramsey-coherent population trapping (CPT) spectrum with the Faraday effect is investi- gated. An experiment is implemented to detect the light polarization components generated from the Faraday effect. The experimental results agree with the theoretical calculations based on the Liouville equation. By comparing with the method without using the Faraday effect, the potential of this method for a CPT-based atomic clock is assessed. The results indicate that this method should improve the short-term frequency stability by several times.
基金supported by the National Natural Science Foundation of China under Grant No. 60671027the Application Basis Research Foundation of Sichuan Province under Grant No. 07JY029-089.
文摘Magneto-optic fiber Bragg gratings (MFBG) based on magneto-optic materials have a lot of potential applications for sensing and optical signal processing. The transmission and reflection spectra of guided optical waves in the MFBG are investigated. According to the sensitivity of MFBG spectral lines to the magneto-optic coupling intensity varying with applied magnetic field, a novel magnetic field sensor of high-resolution up to 0.01 nm/(kA/m) is predicted.
基金supported by National Natural Science Foundation of China (No. 11205119)the Fundamental Research Funds for the Central Universities of China
文摘We investigated in detail how photonic band structures (PBSs) of one dimensional plasma photonic crystals (PPCs) are tuned after being exposed to an external magnetic field. We showed that the properties of PBSs of PPCs are tuned correspondingly because the dielectric constant of the micro plasma layer is modified differently in different frequency ranges due to magneto-optical effects. Two numerical cases are calculated and discussed to study the magneto-optical effects on the properties of PBSs, including the Faraday and Voigt effects.
基金supported by the National Magnetic Confinement Fusion Science Programs of China(Nos.2010GB101002 and 2014GB109001)National Natural Science Foundation of China(Nos.11075048 and 11275059)
文摘A multichannel methanoic acid (HCOOH, λ=432.5 μm) laser interferometer/polarimeter is being developed from the previous eight-channel hydrogen cyanide (HCN, λ=337 μm) laser interferometer in the HL-2A tokamak. A conventional Michelson-type interometer is used for the electron density measurement, and a Dodel-Kunz-type polarimeter is used for the Faraday rotation effect measurement, respectively. Each HCOOH laser can produce a linearly polarized radiation at a power lever of -30 mW, and a power stability 〈10% in 50 rain. A beam waist (diameter d0 ≈12.0 mm, about 200 mm away from the outlet) is finally determined through a chopping modulation technique. The latest optical layout of the interferometer/polarimeter has been finished, and the hardware data processing system based on the fast Fourier transform phase- comparator technique is being explored. In order to demonstrate the feasibility of the diagnostic scheme, two associated bench simulation experiments were carried out in the laboratory, in which the plasma was simulated by a piece of polytetrafluoroethene plate, and the Faraday rotation effect was simulated by a rotating half-wave plate. Simulation results agreed well with the initial experimental conditions. At present, the HCOOH laser interferometer/polarimeter system is being assembled on HL-2A, and is planned to be applied in the 2014-2015 experimental campaign.
文摘A research on passive optical fiber current sensor based on magneto-optical crystal and a new design of light path of the sensor head are presented. Both methods of dual-channel optical detection of the polarization state of the output light and signal processing are proposed. Signal processing can obtain the linear output of the current measurement of the wire more conveniently. Theoretical analysis on the magnetooptical fiber current sensor is given, followed by experiments. After that, further analysis is made according to the results, which leads to clarifying the exiting problems and their placements.
基金supported by the National Natural Science Foundation of China(Nos.U20A20214 and 62275067)。
文摘We demonstrate a high power,Er:Lu AG single-longitudinal-mode laser in an anti-misaligned resonator.Based on the Faraday effect,a 1.61 W single-longitudinal-mode(SLM)laser is obtained with the double corner-cube-retroreflector(CCR)structure,and the tunable wavelength is 1649.2-1650.3 nm.Additionally,we investigate the anti-misalignment characteristics when the CCR moves and rotates along the optical axis.Furthermore,by utilizing the Er:Lu AG amplifier,the maximum 2.32 W single-longitudinal-mode laser at 1649.6 nm is achieved.The beam quality factors M^(2) of the 2.32 W Er:Lu AG single-longitudinal-mode laser are 1.23 and 1.25 along the horizontal(x)and vertical(y)directions,respectively.
基金supported by the National Natural Science Foundation of China (No. 11704361)。
文摘An ultranarrow bandwidth Faraday atomic filter is realized based on cold 87Rb atoms. The atomic filter operates at 780 nm on the 52 S1/2, F = 2 to 52 P3/2, F’= 3 transition with a bandwidth of 7.1(8) MHz, which is approaching the natural linewidth of the transition. The peak transmission achieves 2.6(3)% by the multi-pass probe method. This atomic filter based on cold atoms may find potential applications in self-stabilizing lasers in the future.
基金supported by JSPS KAKENHI (Grant No. 15KK0245)the support and under the auspices of the National Institute for Fusion Science (KEIN1608)+3 种基金co-financed by the European Regional Development Fundthe state budget of the Czech Republic (project Hi LASE Co E: Grant No. CZ.02.1.010.00.015 0060000674)by the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 739573supported by the Ministry of Education, Youth and Sports of the Czech Republic (Programmes NPU I Project No. LO1602, and Large Research Infrastructure Project No. LM2015086)
文摘Faraday effect measurements of holmium oxide(Ho_2O_3) ceramics-based magneto-optical materials, highly potential material candidates for high-energy laser Faraday isolators, are presented in this paper. Temperature dependence of the Verdet constant of nondoped Ho_2O_3 ceramics was measured for temperatures 15–305 K at 1.064 μm wavelength.The Verdet constant dispersion for wavelengths 0.5–1 μm and 1.064 μm was measured for both nondoped Ho_2O_3 ceramics and Ho_2O_3 ceramics doped with terbium Tb3+(0.2 at. %) and cerium Ce3+(0.1 at. %) ions. The results suggest that the relatively low level of doping of Ho_2O_3 with these ions has no significant boosting impact on the Faraday effect. Therefore, other compositions of Ho_2O_3 ceramics-based magneto-optical materials, as well as various doping concentrations, should be further examined.
基金supported by the National Natural Science Foundation of China(Nos.61935002,61975113,and 62275148)the 111 Project(No.D20031),the Shanghai Professional Technical Public Service Platform of Advanced Optical Waveguide Intelligent Manufacturing and Testing(No.19DZ2294000)the Jiangsu Province’s Industry OutlookandKeyCoreTechnologies–KeyProjects(No.BE2022055-4)。
文摘Fiber quarter-wave plates and magneto-optical fibers are important components that greatly affect the sensitivity of fiberoptic current sensors.A Tb:YAG crystal-derived silica fiber(TYDSF)was fabricated using a CO_(2) laser-heating drawing technique.The linear birefringence of TYDSF was measured as 6.661×10^(-6)by a microscope birefringence measurement instrument.A fiber quarter-wave plate was fabricated by TYDSF at 1310 nm,which produced circularly polarized light with a polarization extinction ratio of 0.34 d B.Additionally,the linear birefringence of TYDSF was decreased by 22%by annealing at 750℃ for 7 h,and the Verdet constants of annealed TYDSF were measured to be 9.83,6.67,and 3.48 rad/(T·m)at 808,980,and 1310 nm,respectively.
文摘A novel fiber-optic current sensing scheme is proposed by converting the Faraday rotation to the optical signal's degree of polarization (DOP) change. In this scheme, the lightwave passes through a fiber resonant cavity multiply and experiences Faraday rotation simultaneously. Its main merit is immunity from the environment disturbance to the fiber used in ordinary Faraday rotation sensor. Brief theoretical analysis and simulation are given to show its basic characteristics. Experimental results are demonstrated and the feasibility of the proposed method is also shown.
基金supported by the National Natural Science Foundation of China(Nos.61575139,11474077,11374079,11604236,51602213,61605136 and 11404283)Fundamental&advanced research projects of Chongqing,China(cstc2013jcyjC00001)+3 种基金the Youth Foundation of the Taiyuan University of Technology(No.2015QN066)the Youth Science Foundation of the Taiyuan Institute of Technology(No.2015LQ14)the Science and Technology Program of Guangdong(2016A040403124)the Shanxi Scholarship Council of China(No.2013-037).
文摘We demonstrate an all-optical strategy for realizing spherical three-dimensional(3D)super-resolution(∼λ3/22)spot arrays of pure longitudinal magnetization by exploiting a 4πoptical microscopic setup with two high numerical aperture(NA)objective lenses,which focus and interfere two modulated vectorial beams.Multiple phase filters(MPFs)are designed via an analytical approach derived from the vectorial Debye diffraction theory to modulate the two circularly polarized beams.The system is tailored to constructively interfere the longitudinal magnetization components,while simultaneously destructively interfering the azimuthal ones.As a result,the magnetization field is not only purely longitudinal but also super-resolved in all three dimensions.Furthermore,the MPFs can be designed analytically to control the number and locations of the super-resolved magnetization spots to produce both uniform and nonuniform arrays in a 3D volume.Thus,an all-optical control of all the properties of light-induced magnetization spot arrays has been demonstrated for the first time.These results open up broad applications in magnetic-optical devices such as confocal and multifocal magnetic resonance microscopy,3D ultrahigh-density magneto-optic memory,and light-induced magneto-lithography.
文摘The dynamic performances of magneto-optical Bi-substituted rare-earth iron garnet (BIG) under different external magnetic fields and at different frequencies are experimentally studied. The measurement data indicate that the Faraday rotation angle is almost proportional to the external magnetic field when the garnet is far less saturated, while there is good switch performance when it is saturated. The higher the working frequency is, the larger the saturation magnetic field and the phase delay of Faraday angle relative to the field. The saturation fields and the phase delays at different frequencies are measured. The dynamic performance of the BIG determines the performance of BIG-based optical devices. To get the better performance of such devices, the garnets with small dampness and large stiffness should be chosen elaborately.