Video URL
https://pirsa.org/19020071Decay of correlations in long-range interacting systems at non-zero temperature
APA
Hernandez Santana, S. (2019). Decay of correlations in long-range interacting systems at non-zero temperature. Perimeter Institute for Theoretical Physics. https://pirsa.org/19020071
MLA
Hernandez Santana, Senaida. Decay of correlations in long-range interacting systems at non-zero temperature. Perimeter Institute for Theoretical Physics, Feb. 13, 2019, https://pirsa.org/19020071
BibTex
@misc{ scivideos_PIRSA:19020071, doi = {10.48660/19020071}, url = {https://pirsa.org/19020071}, author = {Hernandez Santana, Senaida}, keywords = {Quantum Information}, language = {en}, title = {Decay of correlations in long-range interacting systems at non-zero temperature}, publisher = {Perimeter Institute for Theoretical Physics}, year = {2019}, month = {feb}, note = {PIRSA:19020071 see, \url{https://scivideos.org/index.php/pirsa/19020071}} }
Senaida Hernandez Santana Institute of Photonic Sciences (ICFO)
Abstract
We study correlations in fermionic systems with long-range interactions in thermal equilibrium. We prove an upper-bound on the correlation decay between anti-commut-ing operators based on long-range Lieb-Robinson type bounds. Our result shows that correlations between such operators in fermionic long-range systems of spatial dimension $D$ with at most two-site interactions decaying algebraically with the distance with an exponent $\alpha \geq 2\,D$, decay at least algebraically with an exponent arbitrarily close to $\alpha$. Our bound is asymptotically tight, which we demonstrate by numerically analysing density-density correlations in a 1D quadratic (free, exactly solvable) model, the Kitaev chain with long-range interactions. Away from the quantum critical point correlations in this model are found to decay asymptotically as slowly as our bound permits.