Photonic Equations of Motion

Journal Article · Fri Sep 17 04:00:00 EDT 2004 · Optics Communications

OSTI ID:883761

Ritchie, A B; Crenshaw, M E

Although the concept of the photon as a quantum particle is sharpened by the quantization of the energy of the classical radiation field in a cavity, the photon's spin has remained a classical degree of freedom. The photon is considered a spin-1 particle, although only two classical polarization states transverse to its direction of propagation are allowed. Effectively therefore the photon is a spin-1/2 particle, although it still obeys Bose-Einstein statistics because the photon-photon interaction is zero. Here they show that the two polarization states of the photon can be quantized using Pauli's spin vector, such that a suitable equation of motion for the photon is Dirac's relativistic wave equation for zero mass and zero charge. Maxwell's equations for a free photon are inferred from the Dirac-field formalism and thus provide proof of this claim. For photons in the presence of electronic sources for electromagnetic fields we posit Lorentz-invariant inhomogeneous photonic equations of motion. Electro-dynamic operator equations are inferred from this modified Dirac-field formalism which reduce to Maxwell's equations if spin-dependent terms in the radiation-matter interaction are dropped.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 883761
• Report Number(s): UCRL-JRNL-206666
• Journal Information: Optics Communications, Journal Name: Optics Communications Journal Issue: 2 Vol. 262; ISSN OPCOB8; ISSN 0030-4018
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BOSE-EINSTEIN STATISTICS
ELECTROMAGNETIC FIELDS
EQUATIONS OF MOTION
PHOTON-PHOTON INTERACTIONS
PHOTONS
POLARIZATION
QUANTIZATION
RADIATIONS
SPIN
WAVE EQUATIONS