map ultisnips snippet to a keymap

Question

I know that by default ultisnips snippet are triggered when the TABkey is pressed. I also know that this trigger key can be changed. However, can a snippet be triggered automatically when certain keys are typed. For example, suppose I have the snippet

snippet mt "Enter math env"
$ $1 $ $0
endsnippet

I can trigger this by typing m t TAB. But can I have this trigger automatically when I type m t, and how can I do that?

Thank you.