Experimental implementation of local adiabatic evolution algorithms by an NMR quantum information processor

Quantum adiabatic algorithm is a method of solving computational problems by evolving the ground state of a slowly varying Hamiltonian. The technique uses evolution of the ground state of a slowly varying Hamiltonian to reach the required output state. In some cases, such as the adiabatic versions of Grover's search algorithm and Deutsch-Jozsa algorithm, applying the global adiabatic evolution yields a complexity similar to their classical algorithms. However, using the local adiabatic evolution, the algorithms given by J. Roland and N. J. Cerf for Grover's search [ Phys. Rev. A. {\bf 65} 042308(2002)] and by Saurya Das, Randy Kobes and Gabor Kunstatter for the Deutsch-Jozsa algorithm [Phys. Rev. A. {\bf 65}, 062301 (2002)], yield a complexity of order $\sqrt{N}$ (where N=2$^{\rm n}$ and n is the number of qubits). In this paper we report the experimental implementation of these local adiabatic evolution algorithms on a two qubit quantum information processor, by Nuclear Magnetic Resonance.Comment: Title changed, Adiabatic Grover's search algorithm added, error analysis modifie

Adiabatic Quantum Computation and Deutsch's Algorithm

We show that by a suitable choice of a time dependent Hamiltonian, Deutsch's algorithm can be implemented by an adiabatic quantum computer. We extend our analysis to the Deutsch-Jozsa problem and estimate the required running time for both global and local adiabatic evolutions.Comment: 6 Pages, Revtex. Typos corrected, references added. Published versio

Applications of Multi-Valued Quantum Algorithms

This paper generalizes both the binary Deutsch-Jozsa and Grover algorithms to $n$-valued logic using the quantum Fourier transform. Our extended Deutsch-Jozsa algorithm is not only able to distinguish between constant and balanced Boolean functions in a single query, but can also find closed expressions for classes of affine logical functions in quantum oracles, accurate to a constant term. Furthermore, our multi-valued extension of the Grover algorithm for quantum database search requires fewer qudits and hence a substantially smaller memory register, as well as fewer wasted information states, to implement. We note several applications of these algorithms and their advantages over the binary cases.Comment: 12 pages, 4 figures; updated version of paper for ISMVL 2007; contains new proof of multi-valued Grover algorithm time complexity, with typos correcte