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تسجيل مستخدم جديدEnergy, momentum, and angular momentum transport mediated by photons
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We set up a general microscopic theory for the transfer of energy, momentum, and angular momentum mediated by photons among arbitrary objects in vacuum together with the environment at infinity. Using the nonequilibrium Greens function for the electromagnetic field and the self energies (polarizability) representing the properties of materials, we derive Meir-Wingreen type formulas for the energy emitted, force, and torque experienced by the objects in a unified formalism. The theory is applied to transport problems of graphene edges under nonequilibrium conditions. We find that the energy radiation of graphene obeys the $T^4$ law with an emissivity of 2.058$%$ that is consistent with both theoretical and experimental work. To generate momentum and angular momentum radiation, potential bias is needed. The observed effects go beyond the predictions of fluctuational electrodynamics.
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