Minimum-energy pulses for quantum logic cannot be shared
- Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701 (United States)
- Graduate School of Information Sciences, Tohoku University, Aoba-ku, Sendai 980-8579 (Japan)
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 N{sup 2}/n. This means that in order to keep the error probability bounded by N{epsilon}, with {epsilon}{approx}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.
- OSTI ID:
- 20976405
- Journal Information:
- Physical Review. A, Vol. 74, Issue 6; Other Information: DOI: 10.1103/PhysRevA.74.060301; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
- Country of Publication:
- United States
- Language:
- English
Similar Records
Optical pulse dynamics for quantum-dot logic operations in a photonic-crystal waveguide
Approximate simulation of quantum channels