We measured the activation energy gap of the N = 2 bubble states using tilted-field technique in two GaAs/AlGaAs samples with Corbino geometry, and observed monotonically decreasing energy gaps with the increasing total magnetic field. The observed tilt angle dependence is discussed based on magneto-orbital coupling and finite-size effect. We also found a bubble state at an uncommon filling factor of 4.67, with an unanticipated energy gap of up to 5.35 K and opposite in-plane field dependence.
@article{arxiv.1706.08829,
title = {Stability of the $N = 2$ bubble states in Corbino geometry under a tilted field},
author = {Pengjie Wang and Yijia Wu and Hua Chen and Ruoxi Zhang and L. N. Pfeiffer and K. W. West and Rui-Rui Du and X. C. Xie and Xi Lin},
journal= {arXiv preprint arXiv:1706.08829},
year = {2017}
}