Detailed Information on Publication Record
2012
Criticality without Frustration for Quantum Spin-1 Chains
BRAVYI, Sergey, Libor CAHA, Ramis MOVASSAGH, Daniel NAGAJ, Peter SHOR et. al.Basic information
Original name
Criticality without Frustration for Quantum Spin-1 Chains
Authors
BRAVYI, Sergey (643 Russian Federation), Libor CAHA (203 Czech Republic, belonging to the institution), Ramis MOVASSAGH (840 United States of America), Daniel NAGAJ (703 Slovakia) and Peter SHOR (840 United States of America)
Edition
Physical Review Letters, COLLEGE PK, Americal Physical Society, 2012, 0031-9007
Other information
Language
English
Type of outcome
Článek v odborném periodiku
Field of Study
10301 Atomic, molecular and chemical physics
Country of publisher
Netherlands
Confidentiality degree
není předmětem státního či obchodního tajemství
Impact factor
Impact factor: 7.943
RIV identification code
RIV/00216224:14330/12:00080251
Organization unit
Faculty of Informatics
UT WoS
000311137600010
Keywords in English
spin chains
Změněno: 22/5/2015 06:30, RNDr. Pavel Šmerk, Ph.D.
Abstract
V originále
Frustration-free (FF) spin chains have a property that their ground state minimizes all individual terms in the chain Hamiltonian. We ask how entangled the ground state of a FF quantum spin-s chain with nearest-neighbor interactions can be for small values of s. While FF spin-1/2 chains are known to have unentangled ground states, the case s 1 remains less explored. We propose the first example of a FF translation-invariant spin-1 chain that has a unique highly entangled ground state and exhibits some signatures of a critical behavior. The ground state can be viewed as the uniform superposition of balanced strings of left and right brackets separated by empty spaces. Entanglement entropy of one half of the chain scales as 1/2 logn + O(1), where n is the number of spins. We prove that the energy gap above the ground state is polynomial in 1/n. The proof relies on a new result concerning statistics of Dyck paths which might be of independent interest.