Laser Tweezers
نویسندگان
چکیده
b) Atoms have some probability of absorbing photons from the laser beam, thereby being kicked along the direction of the beam. This processes can be modelled classically by supposing that the polarizability of the atom has an imaginary part: α = α′ + iα′′. Deduce the (time-averaged) force on an atom along the direction of propagation of a linearly polarized plane electromagnetic wave in terms of α′′, the imaginary (absorptive) part of the polarizability.
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