title: Quantum Computation using Arrays of N Polar Molecules in Pendular States.
abstract: We investigate several aspects of realizing quantum computation using entangled polar molecules in pendular states. Quantum algorithms typically start from a product state |00⋯0⟩ and we show that up to a negligible error, the ground states of polar molecule arrays can be considered as the unentangled qubit basis state |00⋯0⟩ . This state can be prepared by simply allowing the system to reach thermal equilibrium at low temperature (<1 mK). We also evaluate entanglement, characterized by concurrence of pendular state qubits in dipole arrays as governed by the external electric field, dipole-dipole coupling and number N of molecules in the array. In the parameter regime that we consider for quantum computing, we find that qubit entanglement is modest, typically no greater than 10-4, confirming the negligible entanglement in the ground state. We discuss methods for realizing quantum computation in the gate model, measurement-based model, instantaneous quantum polynomial time circuits and the adiabatic model using polar molecules in pendular states.
authors: State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, 200062, China.
authors: Qi
authors: Q
authors: Wei
authors: Department of Computer Science, Purdue University, West Lafayette, IN, 47907, USA.
authors: Yudong
authors: Y
authors: Cao
authors: Department of Chemistry and Physics, Purdue University, West Lafayette, IN, 47907, USA.|Qatar Environment and Energy Research Institute, HBKU, Qatar Foundation, Doha, Qatar.
authors: Sabre
authors: http://orcid.org/0000-0003-0574-5346
authors: S
authors: Kais
authors: Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195, Berlin, Germany.
authors: Bretislav
authors: B
authors: Friedrich
authors: Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, 02138, USA.
authors: Dudley
authors: D
authors: Herschbach
keywords: entanglement; pendular states; polar molecules; quantum computing; superposition