Nuclear magnetic resonance quantum computing exploiting the pure spin state of para hydrogen

Nuclear magnetic resonance (NMR) is used to implement quantum algorithms experimentally. A strategy is presented to increase the sensitivity of a NMR quantum computing experiment. Para hydrogen is used to prepare a density operator in a suitable molecule that is very close to a pure state. An improvement on the order of 10⁴ compared to conventional NMR computing is observed. The technique solving the Deutsch-Jozsa problem based on para hydrogen and Vaska's complex is demonstrated experimentally.