Fast spectroscopic mapping of two-dimensional quantum materials

Berk Zengin,Tohru Kurosawa,Jens Oppliger,Danyang Liu,Lorena Niggli,Fabian D Natterer

doi:10.1103/physrevresearch.3.l042025

Berk Zengin, Tohru Kurosawa + Show 4 more

Open Access

https://doi.org/10.1103/physrevresearch.3.l042025

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Abstract

Spectroscopic mapping refers to the massive recording of spectra whilst varying an additional degree of freedom, such as: magnetic field, location, temperature, or charge carrier concentration. As this involves two serial tasks, spectroscopic mapping can become excruciatingly slow. We demonstrate exponentially faster mapping through our combination of sparse sampling and parallel spectroscopy. We exemplify our concept using quasiparticle interference imaging of Au(111) and Bi2Sr2CaCu2O8 (Bi2212), as two well-known model systems. Our method is accessible, straightforward to implement with existing scanning tunneling microscopes, and can be easily extended to enhance gate or field-mapping spectroscopy. In view of a possible four orders of magnitude speed advantage, it is setting the stage to fundamentally promote the discovery of novel quantum materials.

Highlights

The late Freeman Dyson marveled at the luxury of our times in which scientific progress is strong both in idea and tool-driven research, one occasionally outdoing the other [1]
We examine the necessity for concepts in the field of spectroscopic mapping with the scanning tunneling microscope (STM) as a tool in the discovery of quantum materials
From the beginning of its conception, the STM has been both notorious for its slow measurement pace that is intrinsic to the concept and revered for continually evolving into the tool that provides essential insights into the workings of the microscopic world [3,4,5,6]

Summary

Introduction

The late Freeman Dyson marveled at the luxury of our times in which scientific progress is strong both in idea and tool-driven research, one occasionally outdoing the other [1]. From a Fourier transform of those local density of states (LDOS) measurements, one obtains quasiparticle interference (QPI) information [8,9,10,11,12,13,14,15,16] that provides insight into the band structure of quantum materials.

Results

Conclusion