5 papers
Spin models with critical ground space degeneracy from Lie algebra relations
Andras Molnar, Efekan Kökcü, Norbert Schuch +1
We introduce an -symmetric spin model derived from the algebraic structure of : It is obtained as the nearest-neighbor parent Hamiltonian of a Mat…
Lower Bounds on Spectral Gaps of Parent Hamiltonians via Tensor Networks
Milán Ãdám Rozmán, András Molnár, Norbert Schuch
Proving spectral gaps above the ground space is a central problem in quantum many-body physics. Yet, finding lower bounds on the gap is notoriously difficult. We revisit the martin…
The local characterization of global tensor network eigenstates
José Garre Rubio, András Molnár, Norbert Schuch +1
We study the conditions under which Matrix Product States (MPS) or Matrix Product Operators are exact eigenvectors of an extensive local operator, such as a Hamiltonian. By suitabl…
Direct Equivalence between Dynamics of Quantum Walks and Coupled Classical Oscillators
Lilith Zschetzsche, Refik Mansuroglu, András Molnár +1
Continuous time quantum walks on exponentially large, sparse graphs form a powerful paradigm for quantum computing: On the one hand, they can be efficiently simulated on a quantum…
Two-Dimensional Bialgebras and Quantum Groups: Algebraic Structures and Tensor Network Realizations
José Garre-Rubio, András Molnár, Germán Sierra
We introduce a framework to define coalgebra and bialgebra structures on two-dimensional (2D) square lattices, extending the algebraic theory of Hopf algebras and quantum groups be…