  The next evolutionary step in human-computer interfaces will bring forward
immersive digital experiences that submerge users in a 3D world while allowing
them to interact with virtual or twin objects. Accordingly, various
collaborative extended reality (XR) applications are expected to emerge,
imposing stringent performance requirements on the underlying wireless
connectivity infrastructure. In this paper, we examine how novel multi-antenna
coded caching (CC) techniques can facilitate high-rate low-latency
communications and improve users' quality of experience (QoE) in our envisioned
multi-user XR scenario. Specifically, we discuss how these techniques make it
possible to prioritize the content relevant to wireless bottleneck areas while
enabling the cumulative cache memory of the users to be utilized as an
additional communication resource. In this regard, we first explore recent
advancements in multi-antenna CC that facilitate the efficient use of
distributed in-device memory resources. Then, we review how XR application
requirements are addressed within the third-generation partnership project
(3GPP) framework and how our envisioned XR scenario relates to the foreseen use
cases. Finally, we identify new challenges arising from integrating CC
techniques into multi-user XR scenarios and propose novel solutions to address
them in practice.
