Volume 115, Number 5, September 2016
|Number of page(s)||7|
|Section||Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties|
|Published online||14 October 2016|
Persistent entanglement in a class of eigenstates of quantum Heisenberg spin glasses
1 Department of Physics, Carnegie Mellon University - Pittsburgh, PA, USA
2 Department of Physics, Indian Institute of Science Education and Research - Bhopal, India
3 Department of Physics, Indian Institute of Technology Madras - Chennai, India
Received: 17 April 2016
Accepted: 19 September 2016
The eigenstates of a quantum spin glass Hamiltonian with long-range interaction are examined from the point of view of localisation and entanglement. In particular, low particle sectors are examined and an anomalous family of eigenstates is found that is more delocalised but also has larger inter-spin entanglement. These are then identified as particle-added eigenstates from the one-particle sector. This motivates the introduction and the study of random promoted two-particle states, and it is shown that they may have large delocalisation such as generic random states and scale exactly like them. However, the entanglement as measured by two-spin concurrence displays different scaling with the total number of spins. This shows how for different classes of complex quantum states entanglement can be qualitatively different even if localisation measures such as participation ratio are not.
PACS: 75.10.Nr – Spin-glass and other random models / 03.65.Ud – Entanglement and quantum nonlocality (e.g. EPR paradox, Bell's inequalities, GHZ states, etc.) / 75.50.Lk – Spin glasses and other random magnets
© EPLA, 2016
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.