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arXiv · 1106.3210

Fermionic probes of local quantum criticality in one dimension

Mukund Rangamani·Benjamin Withers
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Abstract

We study the spectral functions of fermionic operators in 1+1 dimensional SU(N) Super Yang-Mills theory with 16 supercharges at finite density using the holographically dual D1-brane geometry. This system exhibits quasi-particle peaks indicating the existence of Fermi points about which excitations have a finite relaxation time, in contrast with the Tomonaga-Luttinger model. The finite width may be attributed to the non-trivial interactions of the probe operators with the background density matrix, modeled holographically as a charged black hole. We show that the fermionic correlators can in fact be deduced from known results for fermion probes of the charged AdS4 black hole background, owing to some remarkable coincidences in supergravity truncations.

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Mukund Rangamani, Benjamin Withers. 2011-06-16. Fermionic probes of local quantum criticality in one dimension. https://doi.org/10.1103/physrevd.84.086003

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