2006/11/13 by Julio Gea-Banacloche, Masanao Ozawa
Computer Science · Mathematics · Physics and Astronomy · #Atom (system on chip) #Bounded function #Computer science #Energy (signal processing) #Mathematical analysis #Mathematics #Photon #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum entanglement #Quantum mechanics #quant-ph
paper · pdf · doi:10.1103/physreva.74.060301
To appear in Phys. Rev. A, Rapid Communications
arxiv created 2006/11/13 · openalex publication_date 2006/12/06 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We show that if an electromagnetic energy pulse in a multimode coherent state with average photon number n is used to carry out the same quantum logical operation on a set of N atoms, either simultaneously or sequentially, the overall error probability in the worst-case scenario (i.e., maximized over all the possible initial atomic states) scales as N2∕n. This means that in order to keep the error probability bounded by Nϵ, with ϵ\ensuremath∼1∕n, one needs to use Nn photons or, equivalently, N separate ``minimum-energy'' pulses: in this sense the pulses cannot, in general, be shared. The origin of this phenomenon is found in atom-field entanglement. These results may have important consequences for quantum logic and, in particular, for large-scale quantum computation.