Designing Efficient Programmable Quantum Circuits
  Constructing general programmable circuits to be able to run any given unitary operator efficiently on a quantum processor is of fundamental importance. We present a new quantum circuit design technique resulting two general programmable circuit schemes. The circuit schemes can be used to simulate any given operator by setting the angle values in the circuit. This provides a fixed circuit design whose angles are determined from the elements of the given matrix, which can be non-unitary, in an efficient way. We also give both classical and quantum complexity analysis for these circuits and show that the circuits require a few classical computations, and the quantum complexities of them are almost the same as non-general circuits. 
Anmer Daskin, Ananth Grama, Giorgos Kollias, Sabre Kais
quant-ph