Impacto
Downloads
Downloads per month over past year
Cirac, J. I. and Pérez García, David and Schuch, N. and Verstraete, F. (2017) Matrix product unitaries: structure, symmetries, and topological invariants. Journal of Statistical Mechanics: Theory and Experiment . 0831051. ISSN 17425468

PDF
761kB  
PDF
Restringido a Repository staff only 3MB 
Official URL: http://iopscience.iop.org/article/10.1088/17425468/aa7e55/meta
URL  URL Type 

http://iopscience.iop.org/  Publisher 
Abstract
Matrix product vectors form the appropriate framework to study and classify onedimensional quantum systems. In this work, we develop the structure theory of matrix product unitary operators (MPUs) which appear e.g. in the description of time evolutions of onedimensional systems. We prove that all MPUs have a strict causal cone, making them quantum cellular automata (QCAs), and derive a canonical form for MPUs which relates different MPU representations of the same unitary through a local gauge. We use this canonical form to prove an index theorem for MPUs which gives the precise conditions under which two MPUs are adiabatically connected, providing an alternative derivation to that of (Gross et al 2012 Commun. Math. Phys. 310 419) for QCAs. We also discuss the effect of symmetries on the MPU classification. In particular, we characterize the tensors corresponding to MPU that are invariant under conjugation, time reversal, or transposition. In the first case, we give a full characterization of all equivalence classes. Finally, we give several examples of MPU possessing different symmetries.
Item Type:  Article 

Uncontrolled Keywords:  Entanglement in extended quantum systems; Quantum information; Tensor network simulations; Topological phases of matte 
Subjects:  Sciences > Mathematics > Topology 
ID Code:  44740 
Deposited On:  22 Sep 2017 11:37 
Last Modified:  12 Feb 2019 11:55 
Origin of downloads
Repository Staff Only: item control page