Google has added a new section to the structured data developer documents named Top Stories With AMP. The page pretty much describes how and where AMP stories show, which is in the top stories news carousel in the mobile search results.
Again, here is how it looks in mobile:
The page just talks about marking up your AMP pages so that Google can pick up the various elements such as the image, your logo, descriptions and so on.
Again, Google added this information in the structured data markup documents:
Aaron Bradley looked at this in more technical detail but ultimately, it is all about making your site AMP ready and marking up the AMP content properly on the page with the structured markup.
Again, AMP went live this week.
Forum discussion at Google+.