Maxwell Equation for Coupled Spin-Charge Wave Propagation

B. Andrei Bernevig, Xiaowei Yu, Shou-Cheng Zhang
2005 Physical Review Letters  
We show that the dissipationless spin current in the ground state of the Rashba model gives rise to a reactive coupling between the spin and charge propagation, which is formally identical to the coupling between the electric and the magnetic fields in the 2+1 dimensional Maxwell equation. This analogy leads to a remarkable prediction that a density packet can spontaneously split into two counter propagation packets, each carrying the opposite spins. In a certain parameter regime, the coupled
more » ... in and charge wave propagates like a transverse "photon". We propose both optical and purely electronic experiments to detect this effect.
doi:10.1103/physrevlett.95.076602 pmid:16196807 fatcat:cox2qvcgpvbeva7tdfhvrhkwuq