Single cream will work fine. I usually warm up very gently the (smoked) salmon and cream in a small milk pan (adding a clove of garlic and/or lemon zest if you like them) and then pour over the pasta when ready. Would probably work well just by mixing full fat Greek yogurt, smoked salmon and perhaps a little dill and then tossing the pasta in it (no heating, otherwise the yogurt separates).
here is one I do all the time - delish! 350g broccoli i small florets 300g salmon fillets 150g pack of soft cheese with garlic and herbs 142lm carton of single cream (or creme fraiche 2 tbsp of sundried tomato paste/puree
Cook the pasta for right time, adding brocoli for last 6 minutes. mix all the other ingredients in a bowl -season to taste - cook the salmon and then flake into the sauce and mix with the pasta and brocoli. Easy!