【摘 要】
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Spin—an intrinsic angular momentum carried by elementary particles—has long been thought to be exclusive to quantum mechanical systems.The spin of photons,for
【机 构】
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Department of Mechanical Engineering,Massachusetts Institute of Technology, USA
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Spin—an intrinsic angular momentum carried by elementary particles—has long been thought to be exclusive to quantum mechanical systems.The spin of photons,for example,is associated with the vectorial nature of electromagnetic waves [1].In classical systems,however,the concept of a spinning degree of freedom is not as well defined.For instance,sound is often considered to be spinless due to the longitudinal and scalar-pressure field description of acoustic waves.
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