I would like to know if we can reference a (tikz)picture within a node from another picture. In this way, I could create a PDF with multiple pictures which give details of each node from my first picture. Thanks.
See section 16.13 Referencing Nodes Outside the Current Pictures in the TikZ/PGF-manual. It shows a nice example on how to do this.
I cite the relevant example below.
Inside the current text we place two pictures, containing nodes named n1 and n2, using
which yields (1), and
yielding the node (2). To connect these nodes, we create another picture using the overlay option and also the remember picture option.
In the manual you will see a line drawn from (1) to (2). I think that shows the possibilities and features of