Quantum computation with biased noise

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Dynamical decoupling techniques are the method of choice for increasing gate fidelities. While these methods have shown very impressive results in decreasing local noise and increasing the fidelities of single qubit operations, these have proven to be more challenging when dealing with noise of two qubit gates. 
The main difficulty arises from the fact that the noise time scale is shorter than the two qubit gate itself and thus refocusing methods are not efficient in this case.
Due to this problem, single qubit gates in several systems have been implemented with a fidelity implying an error rate below the fault-tolerance threshold, while two qubit gates fidelity are still above it, thus creating a set back for fault-tolerant quantum computation.
In this project we present a measurement and feedback based method to refocus two qubit gates, which cannot be refocused by conventional methods. We analyze this method for an error model which is relevant for trapped ions and NV centers quantum information