Populate second column based on People/Group selection

Hi, 

I have a SharePoint list, which contains a list of columns where a users name is selected. This is a Person/Group column so populated from AD. 

Is it possible to add another column to the list to populate the user who is inputted email address or manager - Manager would be better but email address so this could be used for a Vlookup to pull in the Manager name. 

I can't work out how to link one column to another. 

Many Thanks