One of the fastest growing cherry trees is the Kanzan cherry (Prunus serrulata) which is native to Japan, Korea and neighbouring areas. It is primarily grown as an ornamental tree all over the world for its flowers and rarely bears fruit (this is exactly what you want!). If you've ever seen a stock picture of a cherry blossom and thought "WoW!", then most likely, that tree was a Kanzan cherry.

It is also commonly spelled (or misspelled) as "Kwanzan", so if you're searching, you might also want to include that term. From this website that sells trees, Kanzan cherry trees are
- Hardiest of all cherry trees
- Rapidly grows to a mature height of 30-40 ft.
It also says this about the blossoms:
The Kwanzan Flowering Cherry Tree is
easily the showiest of all Cherry
Trees. Its flowers aren’t just pink…
but “Double Pink,” meaning you get
twice as many blooms as found on other
trees.
Although you haven't mentioned what climate you live in, it doesn't seem like it will be a problem, as the tree
Thrives in almost any soil and climate. Easily grown in zones 5-9.