Superradiant instability of charged massive scalar field in Kerr-Newman-anti-de Sitter black hole

Understand

We study the superradiance instability of charged massive scalar field in the background of Kerr-Newman-anti-de Sitter black hole.

• By employing the asymptotic matching technique to solve Klein-Gordon equation analytically, the complex parts of quasinormal frequencies are shown to be positive in the regime of superradiance.
• Because the calculation is performed in the approximation of small black hole, the result indicates that small Kerr-Newman-anti-de Sitter black hole is unstable against the massive scalar field perturbation with small charge.