ajax request returns null but works in postman

I am trying to make my first ajax/api request in laravel 5.3 using vue. The api call works fine in postman but gives me null from the vue request. This is my api defenition:

/**
 * Get all students with a given name
 */
public function students(Request $request) {
    $namePart = $request->namepart ? $request->namepart : '';
    // get all names like namepart
    $students = Student::where('name', 'like', '%' . $namePart . '%')->get();
    return response()->json($students);
}

and the route in routes/api.php

Route::get('/students', 'ApiController@students');

In postman I call this using my (local) url: http://admo/api/students?namepart=spe This returns an array of json objects (i removed the data values)

[
  {
    "id": 8,
    "name": "",
    "address": "",
    "zipcode": "",
    "city": "",
    "email": "",
    "date_of_birth": "",
    "permission_auto_banktransfer": "",
    "bankaccount_name": "",
    "bankaccount_number": "",
    "status": "",
    "created_at": null,
    "updated_at": null
  }
]

This is my vue code:

new Vue({
    el: '#studentlist',
    data: {
        students: []
    },
    mounted: function() {
        this.fetchStudents();
    },
    methods: {
        fetchStudents: function() {
            this.$http.get('api/students?namepart=spe', function(response) {
                this.students = response;
            })
        }
    }
});

in firebug I see the request but it returns null Does anyone see the problem here?

-- Update: if i use jQuery $.ajax instead of this.$http.get it works alright. Something with vue-resource perhaps?