Fundamental research is considered to be any basic or applied research in science and engineering with results that are ordinarily published and shared broadly within the scientific community (see National Security Decision Directive 189). For those who need definitions of basic research and applied research, we offer the following (taken from an OMB guidance document)
The application of knowledge acquired through basic or applied research to meet specific requirements, such as for the production of useful materials or the deployment of certain systems or methods is not considered fundamental research.
Additionally, in order to qualify as fundamental research, the activity must be conducted free of certain kinds of publication (or other types of dissemination) or access restrictions.
If you are still uncertain whether your activity is fundamental research, please contact the Export Control Office.