If you want to pass the controller name as a parameter you can use the following signature:
public static MvcHtmlString ActionLink(
this HtmlHelper htmlHelper,
string linkText,
string actionName,
string controllerName,
Object routeValues,
Object htmlAttributes
)
So, you should use it like this:
@Html.ActionLink("Create Application", "CreateApplication", "Home", null, new { @class = "link" });