Lifshitz black holes in four-dimensional Critical Gravity

Abstract: In this work, we study the existence of asymptotically Lifshitz black holes in Critical Gravity in four dimensions with a negative cosmological constant under two scenarios: First, including dilatonic fields as the matter source, where we find an asymptotically Lifshitz solution for a fixed value of the dynamical exponent $z=4$. As a second case, we also added a non-minimally coupled scalar field $\Phi$ with a potential given by a mass term and a quartic term. Using this approach, we found a solution for $z$ defined in the interval $(1,4)$, recovering the Schwarzchild-Anti-de Sitter case with planar base manifold in the isotropic limit. Moreover, when we analyzed the limiting case $z=4$, we found that there exists an additional solution that can be interpreted as a stealth configuration in which the stealth field is overflying the $z=4$ solution without the non-minimally coupled field $\Phi$. Finally, we studied the non-trivial thermodynamics of these new anisotropic solutions and found that they all satisfy the First Law of Thermodynamics as well as the Smarr relation. We were also able to determine that the non-stealth configuration is thermodynamically preferred in this case.