I found out how to make it from the web search.
The String value for [url=http://www.fileformat.info/info/unicode/char/03b1/index.htm]alpha[/url] is "\u03B1"
So if you define s="\u03B1=2.3"; as a variable in the ejs model and asign s to variable for text field
It should display as what you want. Please check out the attached file.
And it should work for all the operating system.
You can find the unicode for other characters from [url=http://www.fileformat.info/info/unicode/char/search.htm]Unicode Character Search[/url]