Arabic alif-lam ligature

There is a non-standard alif-lam ligature in the Arabic script.
The logo of Al Arabiya shows an example.

Which fonts have such an alif-lam ligature?
Should I write U+0627 ZWJ U+0644 to obtain the ligature? Or
should I write U+0627 ZWNJ U+0644 to prevent the ligature?

Or is alif-lam outside the scope of Unicode and just
regarded as a logo?
Received on Tue Nov 08 2011 - 11:28:00 CST