So the way I see it is that a good Laravel application should be very model- and event-driven.
I have a Model called Article. I wish to send email alert
You've tagged this question as Laravel 5, so I would suggest not using model events as you'll end up with lots of extra code in your models which may make things difficult to manage in future. Instead, my recommendation would be to make use of the command bus and events.
Here's the docs for those features:
http://laravel.com/docs/5.0/bus
http://laravel.com/docs/5.0/events
My recommendation would be to use the following pattern.
There are a few reasons why I like this pattern: Conceptually your commands handle things that are happening right now and events handle things that have just happened. Also, you can easily put command and event handlers onto a queue to be processed later on - this is great for sending emails as you tend not to want to do that in real time as they slow the HTTP request down a fair bit. You can also have multiple event handlers for a single event which is great for separating concerns.
It would be difficult to provide any actual code here as your question more about the concepts of Laravel, so I'd recommend viewing these videos so you get a good idea of how this pattern works:
This one describes the command bus:
https://laracasts.com/lessons/laravel-5-events
This one describes how events work:
https://laracasts.com/lessons/laravel-5-commands