Ember sending query params fails

I am trying to pass a param in my path. i try like this:

route.js

this.route`enter code here`('purchase', {path: '/purchase'}, function () {
        this.route('purchaseDetails');
        this.route('purchaseEdit', {path:'purchaseEdit?country='}); //showing in the URL
        this.route('purchaseReview');
        this.route('purchaseConfirmation');
      });

redirecting like :

this.transitionTo('purchase.purchaseEdit', "SG");

But not works. any one correct me please?