Fault Tolerant Controlled Quantum Dialogue with Logical Brown States Against Collective Noise

In view of the fact that the effects of channel noise are inevitable but easily ignored, we come up with two controlled quantum dialogue(CQD) protocols based on logical Brown states, which are against collective-dephasing and collective-rotation noises, respectively. Compared with existing protocols, there exist several outstanding advantages: firstly, Brown states, as the quantum resource, are the maximally entangled five-qubit states, which own stronger entanglement than GHZ states, W states and cluster states; secondly, the specific quantum circuits are designed to explain how two kinds of logical Brown states, to be strongly against collective noise, are constructed in theory; thirdly, the controller can be offline after quantum resource distribution and permission announcement such that his/her waiting time is effectively reduced; and fourthly, the security analysis manifests that our proposed protocols can not only eliminate the information leakage, but also resist against various well-known attacks, especially the dishonest controller’s attacks.