Superpositions of quantum logic states |0> und |1> are stored and manipulated in the electronic excitation of ions for a future quantum computer . So far, we know how to deal with a single, two [2,3], and up to eight qubits. For a realization of a scalable quantum device we employ linear segmented micro-structured Paul-traps , see figure below. I report on recent progress towards quantum gate operations and experimental studies of non-equilibrium thermodynamics .
As alternative to Paul traps, ions may be confined in the matrix of a solid state crystal. While quantum gate operations have been demonstrated for two of such qubits , no scalable solid state devices have been fabricated. We have proposed a method which uses a linear Paul trap a deterministic source of sympathetically cooled doping ions . Recently, we have proven experimentally deterministic extraction of cold ions.
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10 Minute Talk: Universal Fermi gas in Mixed Dimensions