TY - JOUR T1 - Bounds on quantum communication via Newtonian gravity JF - New Journal of Physics Y1 - 2015 A1 - D. Kafri A1 - G. J. Milburn A1 - J. M. Taylor AB - Newtonian gravity yields specific observable consequences, the most striking of which is the emergence of a $1/r^2$ force. In so far as communication can arise via such interactions between distant particles, we can ask what would be expected for a theory of gravity that only allows classical communication. Many heuristic suggestions for gravity-induced decoherence have this restriction implicitly or explicitly in their construction. Here we show that communication via a $1/r^2$ force has a minimum noise induced in the system when the communication cannot convey quantum information, in a continuous time analogue to Bell's inequalities. Our derived noise bounds provide tight constraints from current experimental results on any theory of gravity that does not allow quantum communication. VL - 17 U4 - 015006 UR - http://arxiv.org/abs/1404.3214v2 CP - 1 J1 - New J. Phys. U5 - 10.1088/1367-2630/17/1/015006 ER - TY - JOUR T1 - A classical channel model for gravitational decoherence JF - New Journal of Physics Y1 - 2014 A1 - D. Kafri A1 - J. M. Taylor A1 - G. J. Milburn AB - We show that, by treating the gravitational interaction between two mechanical resonators as a classical measurement channel, a gravitational decoherence model results that is equivalent to a model first proposed by Diosi. The resulting decoherence model implies that the classically mediated gravitational interaction between two gravitationally coupled resonators cannot create entanglement. The gravitational decoherence rate ( and the complementary heating rate) is of the order of the gravitationally induced normal mode splitting of the two resonators. VL - 16 U4 - 065020 UR - http://arxiv.org/abs/1401.0946v1 CP - 6 J1 - New J. Phys. U5 - 10.1088/1367-2630/16/6/065020 ER - TY - JOUR T1 - Quantum interface between an electrical circuit and a single atom JF - Physical Review Letters Y1 - 2012 A1 - D. Kielpinski A1 - D. Kafri A1 - M. J. Woolley A1 - G. J. Milburn A1 - J. M. Taylor AB - We show how to bridge the divide between atomic systems and electronic devices by engineering a coupling between the motion of a single ion and the quantized electric field of a resonant circuit. Our method can be used to couple the internal state of an ion to the quantized circuit with the same speed as the internal-state coupling between two ions. All the well-known quantum information protocols linking ion internal and motional states can be converted to protocols between circuit photons and ion internal states. Our results enable quantum interfaces between solid state qubits, atomic qubits, and light, and lay the groundwork for a direct quantum connection between electrical and atomic metrology standards. VL - 108 UR - http://arxiv.org/abs/1111.5999v1 CP - 13 J1 - Phys. Rev. Lett. U5 - 10.1103/PhysRevLett.108.130504 ER -