How to send a single line feed (n) to the parent scope?

How can I assign the output of a function to a variable even if said output contains only a single line feed ($'n') ?

For example, the following prints '' but I would expect it to print $'n'.

my_var="$(printf 'n')"
printf '%q' "$my_var"

So my question is how can I get my_var to contain the line feed?

I don’t understand why this:

printf '%q' "$(printf 'n')"

doesn’t give the same output as this:

printf '%q' $'n'