Scalable Fault-Tolerant Quantum Computation in Decoherence-Free Subspaces

Abstract

We investigate how to concatenate different decoherence-free subspaces (DFSs)\nto realize scalable universal fault-tolerant quantum computation. Based on\ntunable $XXZ$ interactions, we present an architecture for scalable quantum\ncomputers which can fault-tolerantly perform universal quantum computation by\nmanipulating only single type of parameter. By using the concept of\ninteraction-free subspaces we eliminate the need to tune the couplings between\nlogical qubits, which further reduces the technical difficulties for\nimplementing quantum computation.\n