The orbital angular momentum (OAM) of beams provides a new dimension, andhave already found lots of applications in various domains. Among suchapplications, the precisely and quantitatively diagnostic of intensity dis...The orbital angular momentum (OAM) of beams provides a new dimension, andhave already found lots of applications in various domains. Among suchapplications, the precisely and quantitatively diagnostic of intensity distributionsamong different OAM modes, namely the OAM spectrum of a beam, is of greatsignificance. In this paper we propose and experimentally validate a simpleinterferential method to achieve this goal. By analyzing the interference patternformed by the beam and a reference field, the OAM spectrum can be obtainedinstantaneously. Furthermore, the proposed method is also available for morecomplex light fields, for instance, the multi-ring optical vortices. In the proof-ofconceptexperiment, the OAM spectra of both single-mode and N-foldmultiplexed OAM modes with various intensity distributions are well detected.Our work offers a new way to precisely measure the OAM spectra of beams andwill advance the development of many applications ranging from classical toquantum physics as the OAM based large-capacity data transmissions, rotationdetection, quantum manipulation and so on.展开更多
A sedimentary geological model is established in order to study the seismic reflection characteristics of channel sand bodies. Synthetic seismic shot gathers are simulated using the acoustic wave equation and then are...A sedimentary geological model is established in order to study the seismic reflection characteristics of channel sand bodies. Synthetic seismic shot gathers are simulated using the acoustic wave equation and then are prestack time migrated. On the imaged data, the reflection characteristics and instantaneous attributes are analyzed and log-constrained impedance inversion is tested. Because of wave field interference, the experimental results show that seismic events do not definitely correspond to the channel sand bodies and that seismic modes of occurrence do not represent the actual ones. The seismic events formed by wave interference may lead to errors and pitfalls in sand body interpretation. The corresponding relations between instantaneous seismic attributes and sedimentary sands are not well established. Log-constrained impedance inversion improves the resolution of channel sands. However, if the inverted resolution is forced to be too high, artifacts related to the initial model may occur.展开更多
基金National Natural Science Foundation of China(NSFC)(11834001,61905012)National Postdoctoral Program for Innovative Talents of China(BX20190036)+2 种基金China Postdoctoral Science Foundation(2019M650015)Beijing Institute of Technology Research Fund Program for Young ScholarsCETC joint research foundation(6141B08231125).
文摘The orbital angular momentum (OAM) of beams provides a new dimension, andhave already found lots of applications in various domains. Among suchapplications, the precisely and quantitatively diagnostic of intensity distributionsamong different OAM modes, namely the OAM spectrum of a beam, is of greatsignificance. In this paper we propose and experimentally validate a simpleinterferential method to achieve this goal. By analyzing the interference patternformed by the beam and a reference field, the OAM spectrum can be obtainedinstantaneously. Furthermore, the proposed method is also available for morecomplex light fields, for instance, the multi-ring optical vortices. In the proof-ofconceptexperiment, the OAM spectra of both single-mode and N-foldmultiplexed OAM modes with various intensity distributions are well detected.Our work offers a new way to precisely measure the OAM spectra of beams andwill advance the development of many applications ranging from classical toquantum physics as the OAM based large-capacity data transmissions, rotationdetection, quantum manipulation and so on.
基金National 973 Key Basic Research Development Program(No.2007CB209608)National 863 High Technology Research Development Program(No.2007AA06Z218)
文摘A sedimentary geological model is established in order to study the seismic reflection characteristics of channel sand bodies. Synthetic seismic shot gathers are simulated using the acoustic wave equation and then are prestack time migrated. On the imaged data, the reflection characteristics and instantaneous attributes are analyzed and log-constrained impedance inversion is tested. Because of wave field interference, the experimental results show that seismic events do not definitely correspond to the channel sand bodies and that seismic modes of occurrence do not represent the actual ones. The seismic events formed by wave interference may lead to errors and pitfalls in sand body interpretation. The corresponding relations between instantaneous seismic attributes and sedimentary sands are not well established. Log-constrained impedance inversion improves the resolution of channel sands. However, if the inverted resolution is forced to be too high, artifacts related to the initial model may occur.
