Efficient multiqubit entanglement via a spin bus.
We propose an experimentally feasible architecture with controllable long-range couplings built up from local exchange interactions. The scheme consists of a spin bus, with strong, always-on interactions, coupled dynamically to external qubits of the Loss and DiVincenzo type. Long-range correlations are enabled by a spectral gap occurring in a finite-size chain. The bus can also form a hub for multiqubit entangling operations. We show how multiqubit gates may be used to efficiently generate W states (an important entanglement resource). The spin bus therefore provides a route for scalable solid-state quantum computation, using currently available experimental resources.
Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA. friesen@cae.wisc.edu
Mark
M
Friesen
Asoka
A
Biswas
Xuedong
X
Hu
Daniel
D
Lidar