Coherent randomized benchmarking

Randomized benchmarking is a powerful technique to efficiently estimate the performance and reliability of quantum gates, circuits devices. Here we propose perform randomized in coherent way, where superpositions different random sequences rather than independent samples are used. We show that this leads uniform simple protocol with significant advantages respect gates can be benchmarked, terms efficiency scalability. e.g. universal gate sets, set $n-$qudit Pauli operators or more general sets including arbitrary unitaries, as well particular Clifford using only set, benchmarked. The price pay an additional complexity add control involved operations. However demonstrate done by auxiliary degrees freedom naturally available basically any physical realization, tested.