%0 Journal Article
%D 2013
%T A noise inequality for classical forces
%A Dvir Kafri
%A J. M. Taylor
%X Lorentz invariance requires local interactions, with force laws such as the Coulomb interaction arising via virtual exchange of force carriers such as photons. Many have considered the possibility that, at long distances or large mass scales, this process changes in some way to lead to classical behavior. Here we hypothesize that classical behavior could be due to an inability of some force carriers to convey entanglement, a characteristic measure of nonlocal, quantum behavior. We then prove that there exists a local test that allows one to verify entanglement generation, falsifying our hypothesis. Crucially, we show that noise measurements can directly verify entanglement generation. This provides a step forward for a wide variety of experimental systems where traditional entanglement tests are challenging, including entanglement generation by gravity alone between macroscopic torsional oscillators.
%8 2013/11/18
%G eng
%U http://arxiv.org/abs/1311.4558v1
%0 Journal Article
%D 2012
%T Algorithmic Cooling of a Quantum Simulator
%A Dvir Kafri
%A J. M. Taylor
%X Controlled quantum mechanical devices provide a means of simulating more complex quantum systems exponentially faster than classical computers. Such "quantum simulators" rely heavily upon being able to prepare the ground state of Hamiltonians, whose properties can be used to calculate correlation functions or even the solution to certain classical computations. While adiabatic preparation remains the primary means of producing such ground states, here we provide a different avenue of preparation: cooling to the ground state via simulated dissipation. This is in direct analogy to contemporary efforts to realize generalized forms of simulated annealing in quantum systems.
%8 2012/07/30
%G eng
%U http://arxiv.org/abs/1207.7111v1
%0 Journal Article
%J New Journal of Physics
%D 2012
%T Quantum Simulation of Spin Models on an Arbitrary Lattice with Trapped Ions
%A Simcha Korenblit
%A Dvir Kafri
%A Wess C. Campbell
%A Rajibul Islam
%A Emily E. Edwards
%A Zhe-Xuan Gong
%A Guin-Dar Lin
%A Luming Duan
%A Jungsang Kim
%A Kihwan Kim
%A Christopher Monroe
%X A collection of trapped atomic ions represents one of the most attractive platforms for the quantum simulation of interacting spin networks and quantum magnetism. Spin-dependent optical dipole forces applied to an ion crystal create long-range effective spin-spin interactions and allow the simulation of spin Hamiltonians that possess nontrivial phases and dynamics. Here we show how appropriate design of laser fields can provide for arbitrary multidimensional spin-spin interaction graphs even for the case of a linear spatial array of ions. This scheme uses currently existing trap technology and is scalable to levels where classical methods of simulation are intractable.
%B New Journal of Physics
%V 14
%P 095024
%8 2012/09/27
%G eng
%U http://arxiv.org/abs/1201.0776v1
%N 9
%! New J. Phys.
%R 10.1088/1367-2630/14/9/095024