Progress Towards Generating a 3D Cluster State via Cold-atom Collisions in an Optical Lattice

Cluster states are highly robust, maximally-entangled states. Among their many novel features, they present a possible route to quantum computation [1]. We will report our progress towards the creation of a 3D cluster state via collisional entangling gates with neutral atoms trapped in a 3D optical lattice [2]. We sort the trapped cesium atoms into a 4x4x3 array. We then cool them so that more than 97% of them are in the 3D vibrational ground state. Next, we prepare all the atoms in an equal superposition of two ground hyperfine states. We then use a state-dependent lattice to spatially split the wave functions of atoms and collide them with their nearest neighbors, before recombining the separated wave functions. By performing this collision procedure sequentially in three directions, we can generate a 3D cluster state. We will characterize the fidelity of this generated 3D cluster state by measuring its stabilizers using our ability to address single atoms.

[1] Raussendorf, R. & Briegel, H. J. Phys. Rev. Lett. 86, 5188–5191 (2001).

[2] Jaksch, D., Briegel, H.-J., Cirac, J. I., Gardiner, C. W. & Zoller, P. Phys. Rev. Lett. 82, 1975-1978 (1999).