Résumé : Fabry–Pérot interferometers have attracted significant attention in recent years as powerful tools to study anyon braiding and explore exotic quantum states. This talk will be divided into two parts. In the first part, I will discuss novel electron pairing and tripling observed in the integer quantum Hall (IQH) regime. Contrary to the conventional understanding that IQH effects can be described by non-interacting theories, I will present evidence from graphene-based quantum Hall FPIs, revealing electron pairing at a bulk filling factor of filling factor 2. More intriguingly, I have also discovered an unexpected emergence of electron tripling, characterized by a fractional Aharonov–Bohm flux period of h/3e at filling factor 3. To unveil these phenomena, we developed a novel plunger-gate spectroscopy, demonstrating that electron pairing (tripling) involves correlated charge transport across two (three) entangled quantum Hall edge channels. This spectroscopy reveals a quantum interference flux periodicity determined by the sum of the phases acquired by distinct edge channels with slightly different interfering areas. In the second part, I will address the “phase jump,” often considered a hallmark of anyon braiding. Interestingly, phase jumps appear in the IQH regime, where anyon is not expected. I will discuss the implications of these findings and their relevance to our understanding of quantum Hall physics.