Quantum systems engineering

Abstract:

We investigate how to create entangled states of ultracold atoms trapped in optical lattices by dynamically manipulating the shape of the lattice potential. We consider an additional potential (the superlattice) that allows both the splitting of each site into a double well potential, and control of the height of the potential barrier between sites. We use superlattice manipulations to perform entangling operations between neighbouring qubits encoded on the Zeeman levels of the atoms without having to perform transfers between the different vibrational states of the atoms. We show how to use superlattices to engineer many-body entangled states resilient to collective dephasing noise. Also, we present a method to realize a two-dimensional (2D) resource for measurement-based quantum computing via Bell-pair measurements. We analyse measurement networks that allow the execution of quantum algorithms while maintaining the resilience properties of the system throughout the computation. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

Abstract:

We analyze the dynamical melting of two-component atomic Mott-Insulator states in a completely-connected optical lattice within the adiabatic approximation. We examine in detail the effect of the dynamical phase acquired by the state during the adiabatic melting of the lattice potential. We show how for certain limits an on-site superposition state with two particles per site melts into a macroscopic superposition state, while an on-site superposition state with only one particle per site melts into a coherent state. © 2008 IOP Publishing Ltd.