Digital sorting of perturbed Laguerre-Gaussian modes by radial index

Bone microstructure often preserves a temporal record of the life history of the animal to which it belongs. Previously used bone microstructure metrics to differentiate between primary bone types are reviewed and tested with a broad sample of bone types. Two new metrics, the radial index and the longitudinal index, are developed to quantitatively differentiate bone types based on bone vascular orientation in three dimensions. All previously used metrics described the bone microstructure in a nonlinear pattern and were unable to separate bone types satisfactorily. The radial index and longitudinal index effectively differentiated bone types and described bone microstructure within a linear continuum. The continuous nature of the range of vascular orientation in bone microstructure necessitates a quantitative approach rather than the commonly used qualitative classifications. The radial index and longitudinal index, which objectively detect small differences in vascular orientation in three dimensions, are therefore preferable to other metrics for inter- and intra-specific comparisons of bone microstructure. These metrics offer novel methods to facilitate examinations of the relationship between primary bone type and ontogeny, biomechanics, and phylogeny.

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Power loss mitigation of orbital-angular-momentum-multiplexed free-space optical links using nonzero radial index Laguerre–Gaussian beams

Journal of the Optical Society of America B ◽

10.1364/josab.34.000001 ◽

2016 ◽

Vol 34 (1) ◽

pp. 1 ◽

Cited By ~ 8

Author(s):

Long Li ◽

Guodong Xie ◽

Yan Yan ◽

Yongxiong Ren ◽

Peicheng Liao ◽

...

Keyword(s):

Angular Momentum ◽

Orbital Angular Momentum ◽

Free Space ◽

Power Loss ◽

Gaussian Beams ◽

Free Space Optical ◽

Loss Mitigation ◽

Optical Links ◽

Radial Index

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Laguerre-Gaussian modes generated vector beam via nonlinear magneto-optical rotation

Scientific Reports ◽

10.1038/s41598-021-85249-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mohsen Ghaderi Goran Abad ◽

Mohammad Mahmoudi

Keyword(s):

Cross Section ◽

Optical Rotation ◽

Beam Cross Section ◽

Free Space Optical ◽

Control Field ◽

Polarization Distribution ◽

Simple Method ◽

Vector Beam ◽

Spatially Distributed ◽

Radial Index

AbstractLaguerre-Gaussian (LG) beams contain a helical phase front with a doughnut-like intensity profile. We use the LG beam to introduce a rather simple method for generation of a vector beam (VB), a beam with spatially-dependent polarization in the beam cross section, via the nonlinear magneto-optical rotation (NMOR). We consider the NMOR of the polarization of a linearly polarized probe field passing through an inverted Y-type four-level quantum system interacting with a LG control field and a static magnetic field. It is shown that the polarization of the transmitted field is spatially distributed by the orbital angular momentum (OAM) of the LG control field, leading to generation of the VB with azimuthally symmetric polarization distribution. We show that the polarization and intensity distributions of the VB spatially vary by changing the OAMs of the LG control field. Moreover, the radial index of the LG control field has a major role in more spatially polarization distributing of the VB. It is shown that the intensity of the generated VBs in different points of the beam cross section can be controlled by the OAM as well as the radial index of the LG control field. However, the VB with highly spatially distributed can be generated for higher values of the radial index of LG control field. The analytical calculations determine the contribution of the different nonlinear (cross-Kerr effect) phenomena on the generation of the VB. We show that the VB is mainly generated via birefringence induced by the applied fields. Finally, we use asymmetric LG (aLG) beams for making the VBs with asymmetric polarization distribution. It is shown that by applying aLG beams, the azimuthal symmetry of the polarization distribution breaks and the asymmetric polarization distribution can be controlled by OAM and radial index of the aLG control field. The obtained results may find more interesting applications in fiber/free space optical communication to enhance the capacity of the information transmission.

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