Implementing logic gates and the Deutsch-Jozsa quantum algorithm by two-dimensional NMR using spin- and transition-selective pulses

Quantum logical operations using two-dimensional NMR have recently been des cribed using the scalar coupling evolution technique [J. Chem. Phys. 109, 1 0603 (1998)]. In the present paper, we describe the implementation of quant um logical operations using two-dimensional NMR, with the help of spin- and transition-selective pulses. A number of logic gates are implemented using two and three qubits with one extra observer spin. Some many-in-one gates (or Portmanteau gates) are also implemented. Toffoli gate (or AND/NAND gate ) and OR/NOR gates are implemented on three qubits. The Deutsch-Jozsa quant um algorithm for one and two qubits, using one extra work qubit, has also b een implemented using spin- and transition-selective pulses after creating a coherent superposition state in the two-dimensional methodology. (C) 2001 Academic Press.