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arXiv · 1802.04191

Massive Dirac fermions from holography

N. W. M. Plantz·F. García Flórez·H. T. C. Stoof
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Abstract

We provide a framework to compute the dynamics of massive Dirac fermions using holography. To this end we consider two bulk Dirac fermions that are coupled via a Yukawa interaction and propagate on a gravitational background in which a mass deformation is introduced. Moreover, we discuss the incorporation of this approach in semiholography. The resulting undoped fermionic spectral functions indeed show that the Yukawa coupling induces a gap in the holographic spectrum, whereas the semiholographic extension is in general gapped but additionally contains a quantum critical point at which the effective fermion mass vanishes and a topological phase transition occurs. Furthermore, when introducing doping, the fermionic spectral functions show a quantum phase transition between a gapped material and a Fermi liquid.

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N. W. M. Plantz, F. García Flórez, H. T. C. Stoof. 2018-04-26. Massive Dirac fermions from holography. https://doi.org/10.1007/jhep04(2018)123

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