Question Summary:
Can Kuffar make usage of Islamic banks?

Question Detail:

can the kuffaar use the muslim banks like Islamic finance banking?

Answer :

In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
If the Islamic Banking is really and strictly conducted according to the Shariah laws of business and economics, then the outcome results in fairness, justice, and equity; which is for the whole of mankind and not only for Muslims.
One should be careful of banks operating in the name of “Islamic Banking” but do not conform to the Shariah laws of Islamic Finance. Any negative consequences of such banks should be attributed to incorrect information and implementation of Islamic Finance and/or mismanagement.
And Allah Ta’āla Knows Best
AbdulMannan Nizami
Student Darul Iftaa
Chicago, IL, USA 
Checked and Approved by,
Mufti Ebrahim Desai.
Daruliftaa.net