title: Quantum galvanometer by interfacing a vibrating nanowire and cold atoms.
abstract: We evaluate the coupling of a Bose-Einstein condensate (BEC) of ultracold, paramagnetic atoms to the magnetic field of the current in a mechanically vibrating carbon nanotube within the frame of a full quantum theory. We find that the interaction is strong enough to sense quantum features of the nanowire current noise spectrum by means of hyperfine-state-selective atom counting. Such a nondestructive measurement of the electric current via its magnetic field corresponds to the classical galvanometer scheme, extended to the quantum regime of charge transport. The calculated high sensitivity of the interaction in the nanowire-BEC hybrid systems opens up the possibility of quantum control, which may be further extended to include other relevant degrees of freedom.
authors: Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, H-1525 Budapest P.O. Box 49, Hungary.
authors: O
authors: O
authors: Kálmán
authors: T
authors: T
authors: Kiss
authors: J
authors: J
authors: Fortágh
authors: P
authors: P
authors: Domokos
mesh_terms: D003080:Cold Temperature; D003198:Computer Simulation; D060526:Magnetic Fields; D008962:Models, Theoretical; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000528:radiation effects*; D011789:Quantum Theory; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D014732:Vibration
chemical_list: D037742:Nanotubes, Carbon