Christina RitzPhD student
Phone: +49 271 740 3536
See also arxiv
Tristan Kraft, Christina Ritz, Nicolas Brunner, Marcus Huber and Otfried Gühne
Characterizing Genuine Multilevel Entanglement
Phys. Rev. Lett. 120, 060502 (2018), arXiv:1707.01050
Entanglement of high-dimensional quantum systems has become increasingly important for quantum communication and experimental tests of nonlocality. However, many effects of high-dimensional entanglement can be simulated by using multiple copies of low-dimensional systems. We present a general theory to characterize those high-dimensional quantum states for which the correlations cannot simply be simulated by low-dimensional systems. Our approach leads to general criteria for detecting multilevel entanglement in multiparticle quantum states, which can be used to verify these phenomena experimentally.
Frank E. S. Steinhoff, Christina Ritz, Nikolai Miklin and Otfried Gühne
Qudit Hypergraph States
Phys. Rev. A 95, 052340 (2017), arXiv:1612.06418
We generalize the class of hypergraph states to multipartite systems of qudits, by means of constructions based on the d-dimensional Pauli group and its normalizer. For simple hypergraphs, the different equivalence classes under local operations are shown to be governed by a greatest common divisor hierarchy. Moreover, the special cases of three qutrits and three ququarts is analysed in detail.