var map = new ol.Map({
  view: new ol.View({
    center: [0, 0],
    zoom: 1
  }),
  layers: [
    new ol.layer.Tile({
      source: new ol.source.MapQuest({layer: 'osm'})
    })
  ],
  target: 'map'
});

//Later on, in a different file
var myMap = $("#map").ol.Map()