Topological order on the Bloch sphere

التفاصيل البيبلوغرافية
العنوان: Topological order on the Bloch sphere
المؤلفون: Liss, Rotem, Mor, Tal, Orus, Roman
المصدر: New J. Phys. 22, 033023 (2020)
سنة النشر: 2018
المجموعة: Condensed Matter
Quantum Physics
مصطلحات موضوعية: Quantum Physics, Condensed Matter - Strongly Correlated Electrons
الوصف: A Bloch sphere is the geometrical representation of an arbitrary two-dimensional Hilbert space. Possible classes of entanglement and separability for the pure and mixed states on the Bloch sphere were suggested by [M. Boyer, R. Liss, T. Mor, PRA 95, 032308 (2017)]. Here we construct a Bloch sphere for the Hilbert space spanned by one of the ground states of Kitaev's toric code model and one of its closest product states. We prove that this sphere contains only one separable state, thus belonging to the fourth class suggested by the said paper. We furthermore study the topological order of the pure states on its surface and conclude that, according to conventional definitions, only one state (the toric code ground state) seems to present non-trivial topological order. We conjecture that most of the states on this Bloch sphere are neither ``trivial'' states (namely, they cannot be generated from a product state using a trivial circuit) nor topologically ordered. In addition, we show that the whole setting can be understood in terms of Grover rotations with gauge symmetry, akin to the quantum search algorithm.
Comment: 15 pages; 5 figures
نوع الوثيقة: Working Paper
DOI: 10.1088/1367-2630/ab7bf2
URL الوصول: http://arxiv.org/abs/1812.00671
رقم الأكسشن: edsarx.1812.00671
قاعدة البيانات: arXiv
الوصف
DOI:10.1088/1367-2630/ab7bf2