Identification and Manipulation of Defects in Black Phosphorus

Area of Science:

• Condensed Matter Physics
• Materials Science
• Surface Science

Background:

• Black phosphorus is a promising 2D material with unique electronic properties.
• Defects significantly influence the properties of 2D materials.
• Understanding and controlling defects is crucial for technological applications.

Purpose of the Study:

• To identify and characterize common defects in black phosphorus.
• To investigate the manipulation of these defects using experimental and computational methods.
• To explore the impact of defect manipulation on the magnetic properties of black phosphorus.

Main Methods:

• Scanning Tunneling Microscopy (STM) for defect imaging and manipulation.
• Density Functional Theory (DFT) calculations for defect analysis and property prediction.
• Development of States Projected Onto Individual Layers (SPOIL) quantities for detailed analysis.

Main Results:

• Identified a ubiquitous defect as a substitutional tin (Sn) impurity in the second sublayer of black phosphorus.
• Characterized another defect as an interstitial Sn atom.
• Demonstrated that an electrical pulse via STM can transform the interstitial Sn defect into a more stable configuration (Sn substitutional + P adatom).
• DFT calculations confirmed this transition induces a switch from a non-magnetic to a magnetic state.
• Introduced SPOIL quantities to correlate atomic/orbital contributions with STM image features.

Conclusions:

• Common defects in black phosphorus, specifically Sn impurities, can be identified and manipulated.
• Pulse-induced manipulation can alter the structural and magnetic properties of black phosphorus.
• SPOIL quantities provide valuable insights into the atomistic origins of STM observations.