QUANTUM, Institut für Physik, Univ. Mainz, Deutschland
Quantum computing with trapped ions and its connection to quantum heat engines
Trapped single ions and ion crystal exhibit excellent control of the internal spin– and the external motional-degree of freedom. Multi-particle quantum entangled states are generated with high fidelity in view of a future quantum processor: Following a scalable approach with ion crystals shuttled in a micro segmented trap we control multi-ion qubit register, obtain long coherence time and demonstrate high fidelity entanglement of s few qubits . However, the model system of a trapped ion crystal may be employed for quantum thermodynamic studies, namely a dynamically driven open quantum system. Initially, we operate a single ion engine and realize four-stroke Otto cycle, thus converting heat into mechanical coherent motion . More recently, we explore spin-dependent light forces  for operating a single ion heat engine fully in the quantum regime  of motion. I will discuss plans for heat engines with ion crystals.
 Bermudez et al, PRX 7, 041061 (2017); Kaufmann et al, PRL 119, 150503 (2017).
 Roßnagel, et al., Science 352, 325 (2016).
 Schmiegelow et al, PRL 116, 033002 (2016).
 von Lindenfels et al, arXiv:1808.02390.
*Este coloquio se llevará a cabo el jueves 1/11 a las 14 hs en el Aula Seminarios del Dpto. de Física, 2º piso pab. I , Ciudad Universitaria.