A. Carlini et A. Hosoya, Quantum computers and unstructured search: finding and counting items withan arbitrarily entangled initial state, PHYS LETT A, 280(3), 2001, pp. 114-120
Grover's quantum algorithm for an unstructured search problem and the COUNT
algorithm by Brassard et al, are generalized to the case when the initial
state is arbitrarily and maximally entangled. This ansatz might be relevant
with quantum subroutines, when the computational qubits and the environmen
t are coupled, and in general when the control over the quantum system is p
artial. (C) 2001 Elsevier Science B.V. All rights reserved.