Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Spin and Orbital Angular Momenta of Electromagnetic Waves: From Classical to Quantum Forms

Wei E. I. Sha, Zhihao Lan, Menglin L. N. Chen, Yongpin P. Chen, Sheng Sun

Abstract

Angular momenta of electromagnetic waves are important both in concepts and applications. In this work, we systematically discuss two types of angular momenta, i.e., spin angular momentum and orbital angular momentum in various cases, e.g., with source and without source, in classical and quantum forms. Numerical results demonstrating how to extract the topological charge of a classical vortex beam by spectral method are also presented.

Spin and Orbital Angular Momenta of Electromagnetic Waves: From Classical to Quantum Forms

Abstract

Angular momenta of electromagnetic waves are important both in concepts and applications. In this work, we systematically discuss two types of angular momenta, i.e., spin angular momentum and orbital angular momentum in various cases, e.g., with source and without source, in classical and quantum forms. Numerical results demonstrating how to extract the topological charge of a classical vortex beam by spectral method are also presented.
Paper Structure (8 sections, 21 equations, 3 figures, 1 table)

This paper contains 8 sections, 21 equations, 3 figures, 1 table.

Table of Contents

  1. Introduction
  2. Theory
  3. Field momentum
  4. Field momentum at source region
  5. Field angular momentum at sourceless region
  6. Quantization of field angular momentum
  7. Numerical Results
  8. Conclusion

Figures (3)

  • Figure 1: A photon incident on an opaque object surface will be (a) reflected back or (b) absorbed, transferring its momentum to the object.
  • Figure 2: Spatial distributions of electric field and OAM density for a vortex beam with the topological charge of $l=2$, (a) amplitude of $E_x$ field; (b) real part of $E_x$ field; (c) real part of $z$ component of OAM density; (d) imaginary part of $z$ component of OAM density.
  • Figure 3: Spatial distributions of electric field and OAM density for a vortex beam with the topological charge of $l=3$, (a) amplitude of $E_x$ field; (b) real part of $E_x$ field; (c) real part of $z$ component of OAM density; (d) imaginary part of $z$ component of OAM density.