Hi Siva,
you can use a sap.ui.core.HTML control to embed any HTML content. This content is then preserved, so it can be a JS widget from a different kind of library.
You can even easily wrap those other widgets/controls as a SAPUI5 widget. One very simple example creates a UI5 control which wraps the GoogleMap API/widget:
http://jsbin.com/aku-test-GoogleMap-as-Notepad-Control/1/edit
(this example is not working in IE because of cross-domain issues when loading UI5 from jsbin.com, so use Chrome, Firefox or so)
Regards
Andreas