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The impact of bound states in Landauer-Buttiker scattering approach to non-equilibrium quantum transport is investigated. We show that the noise power at frequency $ u$ is sensitive to all bound states with energies $omega_b$ satisfying $|omega_b| < u$. We derive the exact expression of the bound state contribution and compare it to the one produced by the scattering states alone. It turns out that the bound states lead to specific modifications of both space and frequency dependence of the total noise power. The theoretical and experimental consequences of this result are discussed.
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