Developments in quantum information processing by nuclear magnetic resonance: Use of quadrupolar and dipolar couplings
- Cite this article as:
- Kumar, A., Ramanathan, K.V., Mahesh, T.S. et al. Pramana - J Phys (2002) 59: 243. doi:10.1007/s12043-002-0114-4
Use of dipolar and quadrupolar couplings for quantum information processing (QIP) by nuclear magnetic resonance (NMR) is described. In these cases, instead of the individual spins being qubits, the 2 n energy levels of the spin-system can be treated as an n-qubit system. It is demonstrated that QIP in such systems can be carried out using transition-selective pulses, in CH3CN, 13CH3CN, 7Li (I=3/2) and 133Cs (I=7/2), oriented in liquid crystals yielding 2 and 3 qubit systems. Creation of pseudopure states, implementation of logic gates and arithmetic operations (half-adder and subtractor) have been carried out in these systems using transition-selective pulses.