Christopher Cheung 張達舜

  • Scholarship in 2022 at Imperial College London

About Christopher Cheung’s work

Christopher Cheung studies materials science, where he is focused on twisted moiré materials, and how their positioning can produce unique characteristics such as insulating and superconducting states.

Twisted moiré materials, which are atomically thin sheets stacked at small relative twist angles, can be used to study the behaviour of correlated electrons in materials. For example, upon stacking two graphene monolayers and rotating them with respect to each other, an additional long-range periodicity that strongly enhances electron correlations emerges. At certain twist angles, unexpected phases are observed, such as unconventional low-temperature superconducting and correlated insulating states. These observations have given rise to the new field of “twistronics” and the possibility to control electrons via the twist angle.

There are many materials that are stable in monolayer form, resulting in a myriad of undiscovered twisted moiré bilayers, but we don’t know which of these systems demonstrate tunable quantum phases. Cheung is developing an efficient and automated multi-scale computer simulation approach to address this question and explore the large chemical space of moiré materials and discover new systems that exhibit promising signatures of strong electron correlations.

Biography

Christopher Cheung is a PhD scholar at Imperial College London, where he was previously an undergraduate student and researcher. He is the winner of the Ken Allen Prize, was on the Imperial College Dean’s List, and won the Outstanding Undergraduate Research.