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We investigate the average steered coherence (ASC) of a central two-qubit system coupled to an XY spin-chain environment. It is shown that there exists subspace in which the initial states are immune to this environment. Outside of this subspace, the decay of the ASC can be significantly suppressed by tuning the interaction of the central qubits and its anisotropy in the z axis, as well as the anisotropy of the spin–spin interaction in the xy plane of the environment and the strength of the transverse magnetic field. For the initial Bell states and their unitary equivalent classes, one can also identify system and environmental parameters for which the ASC oscillates near its maximum even in the long-time interval.

We investigate the average steered coherence (ASC) and maximal steered coherence (MSC) of two qubits in a squeezed generalized amplitude damping channel modeled by a squeezed thermal bath with dissipation and memory. By considering the input Bell states, it is shown that while the dissipation and thermal effects induce decay of the ASC and MSC in the output states, the squeezing effect suppresses their decay in the strong (full) squeezing region for the input even-parity (odd-parity) Bell states. Besides, the memory effect due to correlated actions of the channel can also be exploited for suppressing decay of the ASC and MSC.

Coherence is intrinsically related to projective measurement. When the fixed projective measurement involves higher-rank projectors, the coherence resource is referred to as block coherence, which comes from the superposition of orthogonal subspaces. Here, we establish a set of quantitative relations for the interconversion between block coherence and multipartite entanglement under the framework of the block-incoherent operations. It is found that the converted multipartite entanglement is upper bounded by the initial block coherence of single-party system. Moreover, the generated multipartite entanglement can be transferred to its subsystems and restored to block coherence of the initial single-party system by means of local block-incoherent operations and classical communication. In addition, when only the coarse-grained quantum operations are accessible for the ancillary subsystems, we further demonstrate that a lossless resource interconversion is still realizable, and give a concrete example in three four-level systems. Our results provide a versatile approach to utilize different quantum resources in a cyclic fashion.

The uncertainty principle imposes a limitation on the measurement accuracy of two incompatible observables and has potential applications in quantum information science. We explore the bipartite entropic uncertainty relation and dense coding for two qubits coupled via dipole–dipole interaction and subject to a bosonic reservoir. It is shown that there exists a trade-off between the uncertainty bound and the dense coding capacity which results in their opposite dynamical behaviors. Moreover, the behaviors of the measurement uncertainty and the dense coding capacity rely crucially on the initial system–reservoir correlation, the strength of the dipole–dipole interaction, and the degree of non-Markovianity, and one can reduce the measurement uncertainty and enhance the dense coding capacity by tuning these parameters to appropriate values.

The effect of a reservoir on quantum communication depends on its spectral density. The efficiency of quantum teleportation and dense coding is explored when each one of the channel qubits is coupled simultaneously to multiple bosonic reservoirs. It is shown that the non-Markovianity triggered by increasing the reservoir number can induce revivals of quantum advantages of the two protocols after their disappearance. However, the backflow of information to the system that signifies non-Markovianity does not always induce immediate revivals of the quantum advantages. There may be a delayed effect for some initial states, and only as the backflow of information accumulates to a certain extent can the revivals of quantum advantages be triggered.