I thought xenon was prohibitively expensive to be used as an anesthetic without some crazy recycling systems. How do you even buy it? Aldrich won't sell the unwashed masses lecture bottles of the shit (in fact they can't even provide pricing so that's a sign that it's probably less availiable than you want it to be) and even from a specialty gas company you're gonna be probably into the thousands of dollars for a little cylinder. And they don't make Xe crackers for my whipped cream can.
Also, in general, NMDA antagonists are pretty much the furthest thing from nootropics. All the inhalational anesthetics are pretty firmly in the "reduced cognitive functions" department due to the difficulty of dosing them. I would actually sidle on over to the other side of the periodic table and look at our good friend rubidium - it's a pharmacologically activie monoamine reupatake inhibitor I thought.