The text in a title can be formatted using TeX or LaTeX markup, which means you need to group characters with curly brackets, not parentheses. Something like this:
title('e^{-1000|t|}')
which produces
The markup selection is named in the documentation as the Interpreter, and it clearly describes the three options (LaTeX, TeX, none). There is also an example showing how grouping is achieved (search for "Include Greek Symbols in Title"):
This is a very good introduction on how to write LaTeX expressions:
