Daniel Gottesman

Perimeter Institute
Waterloo Canada

Manifacturing Better Fault-Tolerant Quantum Computer in Ancilla Factories

The threshold result for fault-tolerant quantum computation states that, provided the gate and error rate per time step are below some constant threshold value, arbitrarily long
fault-tolerant quantum computation is possible. The numerical value of the threshold is of considerable interest, as it sets a standard that experimentalists will need to meet to create large quantum computers. Knill has devised circuits using large ancilla factories to create highly reliable ancillas using extensive post-selection to discard bad ancillas, and has done simulations suggesting the threshold error rate is well over 1%. I will describe his construction and give an overview of the rigorous proof (by Aliferis, Preskill, and myself) that the post-selection technique can achieve a threshold of 1/1000.

Seminar schedule: http://www.physics.rutgers.edu/qcg/Seminars.html