Last night I found another item that gives off the focusing decor emotion. The Out of This World Desktop unlocked at level 10 of the Scientist career has a focus decor buff. It does not say in its description that it emits this emotion, but it does (and rather strongly).
My scientist hit level 10, and I happily gave her a new desk with the desktop next to her writer husband. Later I had to tear apart the room trying to figure out why he kept getting focused while writing when he'd always stayed inspired before. I finally had it down to one desk and chair (cheap ones with no emotions), got him nice and inspired, and had him sit in the chair; he stayed inspired. I did the same after putting the Out of This World Desktop on the desk, and he immediately became focused when he entered the room to sit down. I took it back out, and he immediately went back to inspired.