Ferdinand SCHMIDT-KALER
Quantum technologies allow for fully novel schemes of hybrid computing. We employ modern segmented ion traps. I will sketch architectures, the required trap technologies and fabrication methods, control electronics for quantum register reconfigurations, and recent improvements of qubit coherence and gate performance. Currently gate fidelities of 99.995% (single bit) and 99.8% (two bit) are reached. We are implementing a reconfigurable qubit register and have realized multi-qubit entanglement [1] and fault-tolerant syndrome readout [2] in view for topological quantum error correction [3], since current aim is to leave the noisy area of quantum computing. Complementary to gate tomography, we employ thermodynamically-inspired methods within the frameworks of global passivity and passivity deformation where system qubits undergoing unitary evolution but may optionally be coupled also to an unobserved environment qubit, resulting in a heat leak [4].
[1] Kaufmann er al, Phys. Rev. Lett. 119, 150503 (2017)[2] J. Hilder, et al., Phys. Rev. X.12.011032 (2022)
[3] Bermudez, et al, Phys. Rev. X 7, 041061 (2017)
[4] D. Pijn, et al., Phys. Rev. Lett. 128 110601 (2022)