The path to continuous Bose-Einstein condensation

Bose-Einstein condensates (BECs) have transformed quantum science and atomic physics. They are crucial for quantum simulation (Bloch et al., 2012) and sensing (Cronin et al., 2009; Bongs et al., 2019). However, despite long standing efforts quantum gas devices have until recently (Chen et al., 2022) remained restricted to pulsed operation by the need to execute cooling stages time-sequentially. This review discusses the many efforts made towards continuous-wave operation before focusing on our group's approach to achieve continuous-wave Bose-Einstein condensation. Our proof-of-principle demonstration of continuous-wave Bose-Einstein condensation has limitations including low purity, coherence, and the lack of an out coupled atom laser beam. We therefore discuss alternative approaches to make such devices more robust and useful in the future. Finally, we will explore some of the applications that might benefit from the ability to create a continuous source of coherent matter-waves.