Quantum Action-Dependent Channels
It provides a theoretical framework for quantum communication scenarios where the transmitter can influence the channel environment, relevant for quantum memory and communication systems.
This paper generalizes classical action-dependent channels to the quantum domain, where the transmitter's action affects the channel environment before message transmission. Achievable rates are derived for both causal and non-causal channel side information, with a case study on memory storage showing improved performance via action-dependent control.
We study communication over a quantum action-dependent channel, where the transmitter first performs an action that "shocks" the channel environment, and subsequently encodes a message into a transmission sent through the channel. This two-stage interaction arises in various settings, including rewriting over defective memory and quantum effects such as measurement-induced state collapse. Our model can be viewed as a quantum generalization of Weissman's classical action-dependent channel (2010). Here, however, Alice cannot have a copy of the environment state due to the no-cloning theorem. Instead, she may share entanglement with this environment. We derive achievable rates for reliable message transmission via the quantum action-dependent channel, with either causal or non-causal channel side information (CSI). As a case study, we analyze memory storage with depolarization and selective rewriting, demonstrating how action-dependent control influences performance.