首页|A decomposition of light's spin angular momentum density
A decomposition of light's spin angular momentum density
扫码查看
点击上方二维码区域，可以放大扫码查看
原文链接
国家科技期刊平台
NETL
NSTL
万方数据
Light carries intrinsic spin angular momentum(SAM)when the electric or magnetic field vector rotates over time.A familiar vector equation calculates the direction of light's SAM density using the right-hand rule with reference to the electric and magnetic polarisation ellipses.Using Maxwell's equations,this vector equation can be decomposed into a sum of two distinct terms,akin to the well-known Poynting vector decomposition into orbital and spin currents.We present the first general study of this spin decomposition,showing that the two terms,which we call canonical and Poynting spin,are chiral analogies to the canonical and spin momenta of light in its interaction with matter.Like canonical momentum,canonical spin is directly measurable.Both canonical and Poynting spin incorporate spatial variation of the electric and magnetic fields and are influenced by optical vortices.The decomposition allows us to show that a linearly polarised vortex beam,which has no total SAM,can nevertheless exert longitudinal chiral pressure due to equal and opposite canonical and Poynting spins.
Alex J.Vernon、Sebastian Golat、Claire Rigouzzo、Eugene A.Lim、Francisco J.Rodríguez-Fortu?o
展开 >
Department of Physics,King's College London,Strand,London WC2R 2LS,UK
London Centre for Nanotechnology,London,UK
Science and Technology Facilities Council(STFC)Doctoral Training Grant.F.J.R.-F.and S.G.are supported by EIC-Pathfinder-CHIRALFOInnovate UK Horizon Europe GuaranteeEPSRC
国家科技期刊平台
NSTL
万方数据
