This is what i understood from your question :
Your webserver uses cookie to store user session info , you want the user to be redirected to login page when he copy pastes the link onto a new tab .
This is what happens when you do what u said u did :
When a user requests a url from a new tab with an established session in the previous tab , the cookie is sent along with this newtab request hence the webserver renders the page to this request since it is legitimate.
However , the same will not work if you fire the request using a different browser.[In this case the backend will redirect the user to login page (if you've identified the url is without cookie info and programmed a redirect to login page in your server code).]
I don't think this can be done using cookie based session handling .
Please do check this link How to differ sessions in browser-tabs?