Class App\Http\Controllers\StudentController does not exist in Laravel 5

I am building a module called Student in Laravel.

I use the routes.php file inside the Student folder to write routes realted to student module..

When I use just Route::get('/list', function () { return view('welcome');}); program working fine without error.

But when I am using Route::get('/list', 'StudentController@list'); there is a error.

Error is,

Class App\Http\Controllers\StudentController does not exist

Folder Structure

Student Controller

namespace App\Student\Controllers;

use Illuminate\Http\Request;
use App\Http\Controllers\Controller;

class StudentController extends Controller
{
    public function list(){
        echo "Hello"
    }
}

Student Service Provider

namespace App\Student;

use App\Providers\RouteServiceProvider as ServiceProvider;
use Illuminate\Support\Facades\Route;

class StudentServiceProvider extends ServiceProvider
{
    /**
     * Bootstrap the application services.
     *
     * @return void
     */
    public function boot()
    {
        parent::boot();
    }

    /**
     * Register the application services.
     *
     * @return void
     */
    public function register()
    {
        //
    }

    /**
     * Define the routes for the application.
     *
     * @internal param Router $router
     */

    public function map()
    {
        Route::group([
            'namespace' => $this->namespace,
            'prefix' => 'students',
        ], function ($router) {
            require __DIR__ . '/routes.php';
        });
    }
}

via Chebli Mohamed