How a Strange New Substance is Set to Change Technology

🌈 Abstract

The article discusses the discovery that the layered multiferroic material nickel iodide (NiI2) exhibits exceptional magnetoelectric coupling, making it highly suitable for use in high-speed and energy-efficient technologies such as magnetic memories and quantum computing.

🙋 Q&A

[01] Magnetoelectric Coupling in Nickel Iodide

1. What is the key finding about nickel iodide (NiI2)?

• Nickel iodide (NiI2) has greater magnetoelectric coupling than any known material of its kind, making it a prime candidate for technology advances.
• Magnetoelectric coupling means that you can manipulate magnetic properties with an electric field and vice versa, electric properties with magnetic fields.

2. What are the potential applications of materials with strong magnetoelectric coupling like NiI2?

• Magnetic computer memory that is compact, energy efficient, and can be stored and retrieved much faster than existing memory
• Interconnects in quantum computing platforms
• Chemical sensors that can ensure quality control and drug safety in the chemical and pharmaceutical industries

3. What factors contribute to the strong magnetoelectric coupling in NiI2?

• The strong coupling between the electrons' spin and orbital motion on the iodine atoms (a relativistic effect known as spin-orbit coupling)
• The particular form of the magnetic order in nickel iodide, known as a spin spiral or spin helix, which is crucial to initiating the ferroelectric order and for the strength of the magnetoelectric coupling

[02] Research Methodology and Findings

1. How did the researchers study the magnetoelectric coupling in NiI2?

• They excited the material with ultrashort laser pulses in the femtosecond range (a millionth of a billionth of a second) and then tracked the resulting changes in the material's electric and magnetic orders and magnetoelectric coupling via their impact on specific optical properties.

2. What were the key findings from the researchers' calculations?

• The strong spin-orbit coupling on the iodine atoms and the spin spiral/helix magnetic order in NiI2 are the two main factors contributing to its exceptional magnetoelectric coupling.

3. What are the researchers' hopes for future work on NiI2 and similar materials?

• The researchers hope that these groundbreaking insights can be used to identify other materials with similar magnetoelectric properties.
• They also believe that other material engineering techniques could possibly lead to a further enhancement of the magnetoelectric coupling in NiI2.