Is it possible to set multiple models to the core?

hi all

is it possible to set multiple models ( json or odata) to the core by saying

sap.ui.getCore().setModel(oModel,"oModel");

sap.ui.getCore().setModel(jsonModel,"jsonModel" );

so these can be referenced any other controller classes as required. I am setting these 2 models to the core, but while accessing the json model later on, it always returns undefined

var jsonModel = sap.ui.getCore().getModel('jsonModel');

the jsonModel returned here is always undefined.

Regards, Aakash