Preparing Maximally Entangled States By Monitoring the
  Environment-System Interaction In Open Quantum Systems
A common assumption in open quantum systems in general is that the noise
induced by the environment, due to the continuous interaction between a quantum
system and its environment, is responsible for the disappearance of quantum
properties of this quantum system. Interestingly, we show that an environment
can be engineered and controlled to direct an arbitrary quantum system towards
a maximally entangled state and thus can be considered as a resource for
quantum information processing. Barreiro et.al. [Nature 470, 486 (2011)]
demonstrated this idea experimentally using an open-system quantum simulator up
to five trapped ions . In this paper, we direct an arbitrary initial mixed
state of two and four qubits, which is interacting with its environment, into a
maximally entangled state . We use QASM simulator and also an IBM Q real
processor, with and without errors mitigating, to investigate the effect of the
noise on the preparation of the initial mixed state of the qubits in addition
to the population of the target state.
Ali A. Abu-Nada Moataz A. Salhab