Is it possible to use HDMI cable to transfer files between notebooks?

It's technically possible, as HDMI is a bidirectional interface. however, it is designed for packet streams, and not data blocks.

So, in a practical sense, from a users perspective: No, it's not possible.

This doesn't practically help you, but apparently HDMI is being used to stack switches now:

"2 Stacking Ports (HDMI)"

Source: http://www.dell.com/us/fedgov/p/data-center-gigabit/product-compare

It is possible, there are HDMI cables that support data, or even "internet" sharing. Both devices must have support for data transfer.