Qubit-qubit interaction in quantum computers

Physical Review A - Atomic, Molecular, and Optical Physics

Volumn 57, Issue 1, 1998, Pages R1-R4

  Gea Banacloche, Julio ^a  

^a UNIVERSITY OF ARKANSAS   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0002564507     PISSN: 10502947     EISSN: 10941622     Source Type: Journal    
DOI: 10.1103/PhysRevA.57.R1     Document Type: Article

References (16)

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13. This assumes that there are no degeneracies, i.e., that the state |01〉 is distinguishable from |10〉 even in the absence of interaction. This would hold for the NMR computers because of the chemical shifts. In the degenerate case, the evolution model to be used below would become rather complicated, although I do not expect substantial qualitative differences with the present, simpler one.
14. See Ref. 1 for details of the algorithm. Note, however, a typographical error in Eq. (20) of 1, which makes it inconsistent with Eq. (22).
15. A. Barenco, A. Ekert, K.-A. Suominen, and P. Törmä, Phys. Rev. A 54, 139 (1996).
16. I am assuming here that (Formula presented) is “typical,” in that it does not equal a power of 2. Otherwise, (Formula presented) and the factor 0.774 in Eq. (10) below should be equal to 1 instead. My final result (10) may be regarded as a small refinement over the results of 9 regarding the performance of the QFT in the presence of random-phase noise.