Fractional quantum Hall: experiment before theory

How do electrons behave when they’re confined to a single layer, and why do entirely new laws of physics emerge when dimensions shrink?

Papers discussed in this episode:
Experimental observation of the quantum Hall effect and Berry's phase in graphene: https://www.nature.com/articles/nature04235
Tunable Fractional Quantum Hall Phases in Bilayer Graphene: https://arxiv.org/abs/1403.2112
Room-Temperature Quantum Hall Effect in Graphene: https://arxiv.org/abs/cond-mat/0702408

In this episode, we speak with Philip Kim, Harvard physicist and a leading experimentalist in low-dimensional quantum materials. Kim traces the experimental path from high-temperature superconductors and charge-density waves to carbon nanotubes and the earliest graphene devices, revealing how advances in nanofabrication and quantum transport opened the door to modern 2D materials physics.

We dive deep into the Hall effect and quantum Hall effect, from their 19th-century origins to the discovery of quantized and fractional conductance, and explain why these effects were found experimentally before they were fully understood theoretically. Kim shares behind-the-scenes stories of early graphene experiments, mechanical exfoliation, Shubnikov–de Haas oscillations, and what it was like to be scooped by the work that launched graphene into the spotlight.

Along the way, we explore how disorder, dimensionality, and magnetic fields shape electronic behavior; why carbon nanotubes paved the way for graphene; and how many of the most important discoveries in condensed matter physics arise from intuition, timing, and new experimental tools.

Whether you’re interested in graphene, quantum transport, the quantum Hall effect, nanofabrication, superconductors, or the real stories behind breakthrough discoveries, this conversation offers a rare, technically rich look at how modern quantum materials research actually unfolds.

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Timestamps:
00:00 - Intro
01:15 - How Philip Began Studying Graphene
20:06 - Old Methods of Creating Graphene
32:33 - Hall Effect and Quantum Hall Effect
48:29 - Philip's Work at Columbia
52:33 - Philip's First Experiments with Graphene
1:06:43 - Did Philip Get Scooped from a Discovery?
1:09:40 - The Power of Scotch Tape
1:24:57 - High Temperature Quantum Hall Effect
1:30:18 - Fractional Quantum Hall Effect
1:41:17 - Collaboration with Particle Physicists
1:54:13 - Single Layer Graphene
1:59:44 - Next Gen Electronics with 2D Materials
2:03:23 - Graphene Twisting
2:14:48 - Superconductivity in Other Materials
2:20:06 - Anyons
2:30:00 - Fault-Tolerant Quantum Computing
2:36:05 - Can AI and Big Data Help Physicists?
2:40:47 - What Would Philip Do with Unlimited Resources?
2:43:44 - Optimizing the Education System

#graphene #quantumphysics #materialscience #halleffect #electromagnetism