Background: Systematic Literature Reviews are an important research method for gathering and evaluating the available evidence regarding a specific research topic. However, the process of conducting a Systematic Literature Review manually can be difficult and time-consuming. For this reason, researchers aim to semi-automate this process or some of its phases. Aim: We aimed at using a deep-learning based contextualized embeddings clustering technique involving transformer-based language models and a weighted scheme to accelerate the conduction phase of Systematic Literature Reviews for efficiently scanning the initial set of retrieved publications. Method: We performed an experiment using two manually conducted SLRs to evaluate the performance of two deep-learning-based clustering models. These models build on transformer-based deep language models (i.e., BERT and S-BERT) to extract contextualized embeddings on different text levels along with a weighted scheme to cluster similar publications. Results: Our primary results show that clustering based on embedding at paragraph-level using S-BERT-paragraph represents the best performing model setting in terms of optimizing the required parameters such as correctly identifying primary studies, number of additional documents identified as part of the relevant cluster and the execution time of the experiments. Conclusions: The findings indicate that using natural-language-based deep-learning architectures for semi-automating the selection of primary studies can accelerate the scanning and identification process. While our results represent first insights only, such a technique seems to enhance SLR process, promising to help researchers identify the most relevant publications more quickly and efficiently.