The practical construction of scalable quantum computer hardware capable of executing non-trivial quantum algorithms will require the juxtaposition of different types of quantum systems. We analyze a modular ion trap quantum computer architecture with a hierarchy of interactions that can scale to very large numbers of qubits. Local entangling quantum gates between qubit memories within a single register are accomplished using natural interactions between the qubits, and entanglement between separate registers is completed via a probabilistic photonic interface between qubits in different registers, even over large distances. We show that this architecture can be made fault-tolerant, and demonstrate its viability for fault-tolerant execution of modest size quantum circuits.
@article{arxiv.1208.0391,
title = {Large Scale Modular Quantum Computer Architecture with Atomic Memory and Photonic Interconnects},
author = {C. Monroe and R. Raussendorf and A. Ruthven and K. R. Brown and P. Maunz and L. -M. Duan and J. Kim},
journal= {arXiv preprint arXiv:1208.0391},
year = {2014}
}