Realisation of Qudits in Coupled Potential Wells
  Quantum computation strongly relies on the realisation, manipulation and control of qubits. A central method for realizing qubits is by creating a double-well potential system with a significant gap between the first two eigenvalues and the rest. In this work we first revisit the theoretical grounds underlying the double-well qubit dynamics, then proceed to suggest novel extensions of these principles to a triple-well qutrit with periodic boundary conditions, followed by a general d-well analysis of qudits. These analyses are based on representations of the special unitary groups SU(d) which expose the systems' symmetry and employ them for performing computations. We conclude with a few notes on coherence and scalability of d-well systems. 
Ariel Landau, Yakir Aharonov, Eliahu Cohen
quant-ph