Just like
The String is
> "((1 0)(0 1))"
required
>((1 0)(0 1))
I am also using intern function but it returns in form of ((1\ 0)(0\ 1))
You can use read-from-string:
(read-from-string "((1 0)(0 1))")
This function has many parameters and returns two values: the first is what you need, the list:
CL-USER> (car (read-from-string "((1 0)(0 1))"))
(1 0)
You can read about this function in the official documentation.