Daichi Kagamihara, Hironori Kazuta, Yewei Wu, N. J. Fitch, Ippei Danshita
Abstract Recent developments in cloud-based experiment platforms have enabled physicists to examine theoretical concepts with greater accessibility. Oqtant is a cloud-accessible platform for trapped Bose-Einstein Condensates (BECs) of neutral atomic gases, providing an invaluable experimental tool for studying the dynamics of BECs. An intriguing theoretical prediction of a characteristic phenomenon of BECs is anomalous tunneling, whereby low-energy phonon excitations of BECs easily transmit through a barrier potential. We utilize Oqtant to observe the effects of anomalous tunneling on collective excitations of BECs. For this purpose, we theoretically show that anomalous tunneling affects the frequencies of the collective excitations in the low-energy regime, and experimentally measure these frequencies using Oqtant. Our results reveal that low-energy collective modes are less affected by a potential barrier, which indicates the presence of anomalous tunneling. Our work contributes to our fundamental understanding of BECs and highlights the potential of cloud-based experiments in quantum many-body physics.