How to get the active PowerPoint presentation from Excel in office.js?

I'm developing add-in that copy data from Excel to PowerPoint using Yeoman Generator for Office (office.js) but I can't get the opened PowerPoint presentation to write in it.

An Office add-in can only work with the Office application (Excel, Word, PowerPoint, etc.) in which it is open. It cannot reach outside the Office application to work with a document in another Office application.