Skip to content

Filter design for hybrid spin gates

MetadataDetails
Publication Date2015-08-18
JournalPhysical Review A
AuthorsAndreas Albrecht, Martin B. Plenio
InstitutionsUniversitƤt Ulm, Institute of Photonic Sciences
Citations11

The impact of control sequences on the environmental coupling of a quantum\nsystem can be described in terms of a filter. Here we analyze how the coherent\nevolution of two interacting spins subject to periodic control pulses, at the\nexample of a nitrogen vacancy center coupled to a nuclear spin, can be\ndescribed in the filter framework in both the weak and the strong coupling\nlimit. A universal functional dependence around the filter resonances then\nallows for tuning the coupling type and strength. Originally limited to small\nrotation angles, we show how the validity range of the filter description can\nbe extended to the long time limit by time-sliced evolution sequences. Based on\nthat insight, the construction of tunable, noise decoupled, conditional gates\ncomposed of alternating pulse sequences is proposed. In particular such an\napproach can lead to a significant improvement in fidelity as compared to a\nstrictly periodic control sequence. Moreover we analyze the decoherence impact,\nthe relation to the filter for classical noise known from dynamical decoupling\nsequences, and we outline how an alternating sequence can improve spin sensing\nprotocols.\n