Manipulating entanglement of two qubits in a common environment by means of weak measurements and quantum measurement reversals

摘要

Addressing various types of decoherence is of paramount importance for employing entanglement innquantum information processing and quantum computing. In this paper, we propose two schemes to manipulatenentanglement of two qubits stored in a common environment by means of combined weak measurements andnquantum measurement reversals. We derive the explicit conditions for the measurement strengths under whichnat any time and for any initial states the qubits’ entanglement can be protected quite well with a reasonable finitensuccess probability. Moreover, the two schemes enable us in principle to achieve the maximal entanglement ornto restore the initial state (entanglement) of the qubits.