



01472nas a2200145   4500008004100000022001400041245007400055210006900129260001400198490000800212520103000220100002101250700001801271856003701289       2020                        eng d  a2469-995000aCoherent transport of spin by adiabatic passage in quantum dot arrays0 aCoherent transport of spin by adiabatic passage in quantum dot a  c9/17/20200 v1023 a<p>We introduce an adiabatic transfer protocol for spin states in large quantum dot arrays that is based on time-dependent modulation of the Heisenberg exchange interaction in the presence of a magnetic field gradient. We refer to this protocol as spin-CTAP (coherent transport by adiabatic passage) in analogy to a related protocol developed for charge state transfer in quantum dot arrays. The insensitivity of this adiabatic protocol to pulse imperfections has potential advantages for reading out extended spin qubit arrays. When the static exchange interaction varies across the array, a quantum-controlled version of spin-CTAP is possible, where the transfer process is conditional on the spin states in the middle of the array. This conditional operation can be used to generate N-qubit entangled GHZ states. Using a realistic noise model, we analyze the robustness of the spin-CTAP operations and find that high-fidelity (&gt;95%) spin eigenstate transfer and GHZ state preparation is feasible in current devices.</p>1 aGullans, Michael1 aPetta, J., R.  uhttps://arxiv.org/abs/2007.10582