This research has the aim to investigate the large pre-diffusion period for two
technologies: quantum cryptography and nuclear fusion power plants. Both technologies originate from basic physics research, have a high societal value and are a business to business product. First, a status overview of the technologies is given together with its principles and (dis)advantages. Hereafter, the high-tech products are positioned in a life cycle pattern and pre-defined factors that could create a barrier to large scale diffusion are investigated.

In the following chapters, other literature is investigated and different reasons for a long pre-diffusion period are explored. The literature that is used to determine the position in the life cycle pattern and investigation of factors, is critically reviewed and discussed. Different factors outside the existing framework are found that apply to the cases of quantum cryptography and nuclear fusion power plants. Additionally, a bias due to the telecom industry data that has been used to build the framework has been observed in different aspects of the diffusion theory.
This research is conducted by the means of a comparative case study, including a literature review and the opinion of an expert.

The final delivery of this research is a proposition for an extended diffusion theory and a thorough discussion on validity and decision making within the framework. In this proposition the diffusion theory is extended with additional factors: type of funding, potential misuse of a technology, competition, managing expectations and a case specific factor. The current and additional factors are categorized into different types of factors. Additionally, a distinction between niche applications, innovations and split-offs in the life cycle pattern is made and discussed. Finally, notes on the validity of the assessment of factors are given.