Can I create record in Ember without the record name

My Backend Rails API consumes POST requests in the form of

{
    "name": "Mark White",
    "email" : "mark@xyz.com"
}

Have tried this in Postman and this creates a record successfully.

In my ember frontend, Im using the following code to create a new record, from a form input:

app/routes/addUser.js

import Ember from 'ember';

export default Ember.Route.extend({
  actions: {
        addUser(){
            let formData = {
                "name": this.controller.get('name'),
                "poster_url": this.controller.get('email')
            };

            let newUser = this.store.createRecord('user',formData);
            newUser.save();
       }
  }

});

which generates the request as

{
  "user": {
    "name": "Mark White",
    "email" : "mark@xyz.com"
  }
}

which my backend is not prepared to handle and throws an error.

Any way I can quickly conform to the json format that works for me in Postman.