Suppressing nematicity in FeSe through exfoliation

The role of nematicity in iron-based superconductors has served as a long-standing challenge regarding how to understand their unique electronic features. How nematicity influence superconductivity and quantum criticality remains an unanswered question. Therefore, a method to control nematicity in iron-based superconductors can provide a pathway to further explore their competing phases. Here, we demonstrate that simple mechanical exfoliation can suppress nematicity in FeSe, an iron-based superconductor. From Raman spectroscopy and transport experiment, we show a clear absence of nematic order in thin FeSe flakes, despite being present in bulk crystals. This shows exfoliation can engineer collective phenomena in FeSe and provide a platform to further explore emergent physics.