Exploration of quantum correlations in an open system with Unruh effect under a Schwarzschild space-time

In this letter, we investigate quantum correlations (quantum discord, concurrence and Bell nonlocality) in an open system (amplitude damping channel) with the Unruh effect under a Schwarzschild space-time. In an amplitude damping (AD) channel, we can discover that the Hawking–Unruh effects and decoherence will influence these quantum correlations. However, quantum correlations always decrease with increasing the AD decoherence strength, irrespective of whether there are Hawking–Unruh effects. The results also indicate that the impact of the AD decoherence on quantum correlations is stronger than that of the Hawking–Unruh effects. Besides, we find that if concurrence is present, Bell nonlocality may disappear. This means that the Bell nonlocal states are a strict subset of the entangled states. Furthermore, the redistributions of quantum correlations are discussed in detail under a Schwarzschild space-time. The results show that the reduced physically accessible quantum correlations can be redistributed to the physically inaccessible regions. (letter)