This cannot be done using just configurations. You will need to query the User Profile Service and get the Display Name using the login name the search service returns.
For obtaining any property you can use something like this:
function getProfilePropertyValueFromLoginName(loginName, propertyName, success, error) {
// Get the current client context and PeopleManager instance.
var clientContext = new SP.ClientContext.get_current();
var peopleManager = new SP.UserProfiles.PeopleManager(clientContext);
// Get user properties for the target user.
// To get the PersonProperties object for the current user, use the
// getMyProperties method.
var personProperties = peopleManager.getPropertiesFor(loginName);
// Load the PersonProperties object and send the request.
clientContext.load(personProperties);
clientContext.executeQueryAsync(
function () {
if (success) {
success(loginName, personProperties.get_userProfileProperties()[propertyName]);
}
}, function (sender, args) {
if (error) {
error(sender, args);
}
});
}
-Hope it helps