We report the experimental observation of two-dimensional Talbot effect when a resonance plane wave interacts with a two-dimensional atomic density grating generated by standing wave manipulation of ultracold Bose gas...We report the experimental observation of two-dimensional Talbot effect when a resonance plane wave interacts with a two-dimensional atomic density grating generated by standing wave manipulation of ultracold Bose gases. Clear self-images of the grating and sub-images with reversed phase or fractal patterns are observed. By calculating the autocorrelation functions of the images, the behavior of periodic Talbot images is studied. The Talbot effect with two-dimensional atomic density grating expands the applications of the Talbot effect in a wide variety of research fields.展开更多
The reflection Talbot effect under the illumination of Gaussian spherical wave and plane wave is observed on 1D and 2D photonic crystal of silicon prepared by nanosecond laser. It is found that the distance between tw...The reflection Talbot effect under the illumination of Gaussian spherical wave and plane wave is observed on 1D and 2D photonic crystal of silicon prepared by nanosecond laser. It is found that the distance between two adjacent Talbot images increases lineally with increasing of image distance as well as amplification of Talbot images under the illumination of Gaussian spherical wave. The result of theory is coincident with that of experiment, which shows that selecting suitable wavefront shape of input field can enlarge the amplification rate and improve the resolution of Talbot imaging. The reflection Talbot effect will have a lot of good application in microscopy of micro-fabrication on silicon, such as detecting period structures of plasma on line of PLD fabricating.展开更多
We investigated the Talbot effect in an anti-parity-time(PT)symmetric synthetic photonic lattice composed of two coupled fiber loops.We calculated the band structures and found that with an increase in the gain-loss p...We investigated the Talbot effect in an anti-parity-time(PT)symmetric synthetic photonic lattice composed of two coupled fiber loops.We calculated the band structures and found that with an increase in the gain-loss parameter,the band transitions from a real spectrum to a complex spectrum.We study the influence of phase in the Hermitian operator on the Talbot effect,and the Talbot effect disappears when the period of the input field is N>8.Further study shows that the variation of Talbot distance can also be modulated by non-Hermitian coefficients of gain and loss.This work may find significant applications in pulse repetition-rate multiplication,temporal invisibility,and tunable intensity amplifiers.展开更多
In this study,we report on the fractional Talbot ffect of nonpar axial self-accelerating beams in a multilevel electromagnetically induced transparency(EIT)atomic configuration,which,to the best of our knowledge,is th...In this study,we report on the fractional Talbot ffect of nonpar axial self-accelerating beams in a multilevel electromagnetically induced transparency(EIT)atomic configuration,which,to the best of our knowledge,is the first study on this subject.The Tallbot ffect originates from superposed eigenmodes of the Helmholtz equation and forms in the EIT window in the presence of both linear and cubic susceptibilities.The Talbot ffect can be realized by appropriately selecting the cofficients of the beam components.Our results indicate that the larger the radial difference between beam components,the stronger the interference between them,the smaller the Tallbot angle is.The results of this study can be useful when studying optical imaging.optical measurements,and optical computing.展开更多
We investigate the Airy–Talbot effect of an Airy pulse train in time-dependent linear potentials.The parabolic trajectory of self-imaging depends on both the dispersion sign and the linear potential gradient.By impos...We investigate the Airy–Talbot effect of an Airy pulse train in time-dependent linear potentials.The parabolic trajectory of self-imaging depends on both the dispersion sign and the linear potential gradient.By imposing linear phase modulations on the pulse train,the Airy–Talbot effects accompanied with positive and negative refractions are realized.For an input composed of stationary Airy pulses,the self-imaging follows straight lines,and the Airy–Talbot distance can be engineered by varying the linear potential gradient.The effect is also achieved in symmetric linear potentials.The study provides opportunities to control the self-imaging of aperiodic optical fields in time dimension.展开更多
从双缝干涉的简单理论出发,将光栅分解为许多组双缝,利用人们熟知的干涉条纹间距公式导出Talbot成像位置,结论与Talbot效应公式一致。并由实验证实,在(2 m 1)d2/λ(m为正整数)的位置得到的为横向平移d/2的周期像,并非原周期性物的负反...从双缝干涉的简单理论出发,将光栅分解为许多组双缝,利用人们熟知的干涉条纹间距公式导出Talbot成像位置,结论与Talbot效应公式一致。并由实验证实,在(2 m 1)d2/λ(m为正整数)的位置得到的为横向平移d/2的周期像,并非原周期性物的负反差像。展开更多
基金Supported by the State Key Development Program for Basic Research of China under Grant No 2016YFA0301501the National Natural Science Foundation of China under Grant Nos 11504328,61475007,11334001 and 91336103
文摘We report the experimental observation of two-dimensional Talbot effect when a resonance plane wave interacts with a two-dimensional atomic density grating generated by standing wave manipulation of ultracold Bose gases. Clear self-images of the grating and sub-images with reversed phase or fractal patterns are observed. By calculating the autocorrelation functions of the images, the behavior of periodic Talbot images is studied. The Talbot effect with two-dimensional atomic density grating expands the applications of the Talbot effect in a wide variety of research fields.
基金Support from the National Natural Science Foundation of China ( Grant No. 11264007 )from the National Key Laboratory of Surface Physics in Fudan University
文摘The reflection Talbot effect under the illumination of Gaussian spherical wave and plane wave is observed on 1D and 2D photonic crystal of silicon prepared by nanosecond laser. It is found that the distance between two adjacent Talbot images increases lineally with increasing of image distance as well as amplification of Talbot images under the illumination of Gaussian spherical wave. The result of theory is coincident with that of experiment, which shows that selecting suitable wavefront shape of input field can enlarge the amplification rate and improve the resolution of Talbot imaging. The reflection Talbot effect will have a lot of good application in microscopy of micro-fabrication on silicon, such as detecting period structures of plasma on line of PLD fabricating.
基金supported by the National Key Research and Development Program of China(Nos.2022YFA1404800 and 2019YFA0705000)the National Natural Science Foundation of China(Nos.12104272,12274270,91950104,12192254,92250304,and 11974218)the Local Science and Technology Development Project of the Central Government(No.YDZX20203700001766)。
文摘We investigated the Talbot effect in an anti-parity-time(PT)symmetric synthetic photonic lattice composed of two coupled fiber loops.We calculated the band structures and found that with an increase in the gain-loss parameter,the band transitions from a real spectrum to a complex spectrum.We study the influence of phase in the Hermitian operator on the Talbot effect,and the Talbot effect disappears when the period of the input field is N>8.Further study shows that the variation of Talbot distance can also be modulated by non-Hermitian coefficients of gain and loss.This work may find significant applications in pulse repetition-rate multiplication,temporal invisibility,and tunable intensity amplifiers.
基金the National Natural Science Foundation of China(Grant Nos.61805068,11747046,and 61875053)China Postdoctoral Science Foundation(CPSF)(Grant No.2017M620300)+1 种基金the Natural Science Fund of Shaanxi Province(Grant No.2018JQ6002)the Science and Technology Department of Henan Province(Grant No.202102210111).
文摘In this study,we report on the fractional Talbot ffect of nonpar axial self-accelerating beams in a multilevel electromagnetically induced transparency(EIT)atomic configuration,which,to the best of our knowledge,is the first study on this subject.The Tallbot ffect originates from superposed eigenmodes of the Helmholtz equation and forms in the EIT window in the presence of both linear and cubic susceptibilities.The Talbot ffect can be realized by appropriately selecting the cofficients of the beam components.Our results indicate that the larger the radial difference between beam components,the stronger the interference between them,the smaller the Tallbot angle is.The results of this study can be useful when studying optical imaging.optical measurements,and optical computing.
基金supported by the National Natural Science Foundation of China(Nos.11674117 and 11974124)。
文摘We investigate the Airy–Talbot effect of an Airy pulse train in time-dependent linear potentials.The parabolic trajectory of self-imaging depends on both the dispersion sign and the linear potential gradient.By imposing linear phase modulations on the pulse train,the Airy–Talbot effects accompanied with positive and negative refractions are realized.For an input composed of stationary Airy pulses,the self-imaging follows straight lines,and the Airy–Talbot distance can be engineered by varying the linear potential gradient.The effect is also achieved in symmetric linear potentials.The study provides opportunities to control the self-imaging of aperiodic optical fields in time dimension.
