Laravel 5.2 Auth::attempt 验证后，关掉浏览器再打开还是登陆状态，没有登出？

public function login(Request $request){

        if (Auth::attempt(['name' => $request->get('name'), 'password' => $request->get('password')])) {

            // 认证通过...

            return redirect()->intended('/admin');

        }else{

            return 'login fail';

        }

    }