A meetinthemiddle algorithm for fast synthesis of depthoptimal quantum circuits
Abstract
We present an algorithm for computing depthoptimal decompositions of logical operations, leveraging a meetinthemiddle technique to provide a significant speedup over simple brute force algorithms. As an illustration of our method we implemented this algorithm and found factorizations of the commonly used quantum logical operations into elementary gates in the Clifford+T set. In particular, we report a decomposition of the Toffoli gate over the set of Clifford and T gates. Our decomposition achieves a total Tdepth of 3, thereby providing a 40% reduction over the previously best known decomposition for the Toffoli gate. Due to the size of the search space the algorithm is only practical for small parameters, such as the number of qubits, and the number of gates in an optimal implementation.
 Publication:

arXiv eprints
 Pub Date:
 June 2012
 arXiv:
 arXiv:1206.0758
 Bibcode:
 2012arXiv1206.0758A
 Keywords:

 Quantum Physics;
 Computer Science  Emerging Technologies
 EPrint:
 23 pages, 15 figures, 1 table