Coulomb blockade effects in capacitively coupled quantum dots can be utilized for constructing an N-qubit system with antiferromagnetic Ising interactions. Starting from the tunneling Hamiltonian, we theoretically show that the Hamiltonian for a weakly coupled quantum-dot array is reduced to that for nuclear magnetic resonance (NMR) spectroscopy. Quantum operations are carried out by applying only electrical pulse sequences. Thus various error-correction methods developed in NMR spectroscopy

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... NMR quantum computers are applicable without using magnetic fields. A possible measurement scheme in an N-qubit system is quantitatively discussed.