Tunable Colloidal Synthesis Enabling {\mu}-ARPES on Individual Two-dimensional Bismuth Nanocrystals

TL;DR

This paper presents a scalable colloidal synthesis method for high-quality two-dimensional bismuth nanosheets with tunable sizes, enabling detailed ARPES characterization and advancing their application in quantum and energy technologies.

Contribution

It introduces a controlled colloidal synthesis technique for Bi nanosheets with specific size and structural properties, facilitating rapid production and analysis.

Findings

Nanosheets have tunable lateral sizes from 0.6 to 4.1 micrometers.

ARPES measurements match DFT calculations, confirming high crystal quality.

Nanosheets exhibit excellent oxidation resistance and ambient stability.

Abstract

Two-dimensional bismuth (Bi) is a promising platform for quantum and energy technologies due to strong spin-orbit coupling, high thermoelectric efficiency, and magnetoresistance. However, scalable and flexible synthesis of high-quality Bi with fast research turnaround remains challenging. We report a controlled colloidal synthesis of Bi nanosheets with tunable lateral sizes (0.6 - 4.1 um), hexagonal shape, and a layered single-crystalline structure along the {00l} planes. The nanosheets exhibit excellent oxidation resistance and ambient stability. ARPES measurements on individual nanosheets reveal a band structure in excellent agreement with DFT calculations, confirming high crystal quality and uniformity. Our findings enable fast production and characterization of two-dimensional Bi, paving the way for fundamental studies and integration into next-generation quantum and energy devices.