How can I perform MongoDB query asynchronously in PHP?

How can I perform MongoDB query asynchronously in PHP?

For MySQL we can use

``` php
 <?php
    mysqli_query ( $link , $query,MYSQLI_ASYNC);
    mysqli::poll ( $read , $error , $reject , $sec,$usec );
    mysqli_reap_async_query ( $link );
```

How would somebody perform the above task in MongoDB?
