Quantum Matter Design Studio Begins Imaging Quantum Materials — Down to the Atomic Scale

Assistant Professor Christopher Gutierrez

Within solids, quantum effects can lead to vast numbers of electrons cooperating to form new, emergent phases of matter. That is, electrons lose their individual identities and instead display spectacular collective behavior, such as forming macroscopic quantum condensates or even states with fractional charge.

But how can one see this otherwise hidden quantum world inside of solids? In the Quantum Matter Design Studio led by Assistant Professor Christopher Gutiérrez, researchers harness two key quantum mechanical effects to visualize this novel electronic behavior: the quantum tunneling and photoelectric effects. Scanning tunneling microscopy/spectroscopy (STM/S) provides stunning sub-atomic resolution images of quantum behavior by recording the (extremely tiny!) electronic quantum tunnel current between a sharp metallic tip and a material’s surface. Angle-resolved photoemission spectroscopy (ARPES), meanwhile, harnesses the photoelectric effect to directly visualize the energy-momentum structure of electrons within solids.

Together, these complementary techniques allow for a detailed exploration of the novel physics of quantum materials. After joining UCLA in the COVID-affected Fall of 2020, the Quantum Matter Design Studio imaged its first photoemission spectrum by  the end of 2021 and its very first atoms in late 2022! Current research projects include visualizing the atomic-scale sliding dynamics of quantum condensates; using atom-by-atom assembly to create exotic fractionalized electron states in two-dimensional materials; and using large physical strain-fields to tune the properties of correlated materials (funded by a UBC-UCLA Collaborative Research Mobility Award). In Fall 2023, PhD Bridge student and group member Asari Prado was awarded a prestigious NSF Graduate Research Fellowship to study how adsorbed atoms and atomic defects can create exotic electronic phases in two-dimensional “graphene,” which is a single atomic layer of ordinary graphite – the same in your pencil lead!