Credit
Ella Maru Studio
Columbia University researchers have proven that quantum fluctuations from a vacuum can modify nearby materials. By matching the vibrations of 2D flakes to a superconductor, they successfully suppressed its properties, unlocking a new method for material engineering
Researchers have confirmed that the “empty” space within atom-thin materials is not truly still but rather a source of quantum fluctuations that can drastically change the properties of nearby crystals.
Led by Columbia University, a collaborative study published in Nature demonstrates how these fluctuations can suppress superconductivity in a neighbouring material without the need for external triggers like heat or lasers.
This discovery realises a theoretical “holy grail” that scientists have pursued for decades, offering an entirely new method for material engineering.
The power of matching vibrations: Quantum fluctuations
Quantum fluctuations exist even at ultracold temperatures where classical motion stops. These fluctuations create electromagnetic environments that can interact with matter. The researchers discovered that by placing a nanometer-sized flake of hexagonal Boron Nitride (hBN) on top of a superconducting crystal known as κ-ET, they could halt the superconducting state.
The mechanism relies on matching resonances. The quantum vibrations within the layers of hBN happen to vibrate at the same frequency as those in the κ-ET crystal. When these vibrations match, they interact, altering the electromagnetic environment in a way that prevents electrons from reaching the collective state required for superconductivity.
Testing hBN against materials with different resonances produced no effect, confirming that the interaction is specifically tuned to the material’s internal “vibrations.”
Using 2D materials as quantum cavities
In physics, a cavity is a structure that confines electromagnetic waves. While cavities are traditionally made with mirrors, the team utilised hBN as a nano-scale cavity. Because hBN is a hyperbolic material, it naturally enhances internal vibrations. This allows even the incredibly small fluctuations found in a vacuum to have a massive impact on surrounding matter.
To prove that the effect was caused solely by quantum fluctuations and not by light, the team conducted experiments in total darkness. Using a cryogenic magnetic force microscope (MFM), they detected the Meissner effect—the repulsion between a magnet and a superconductor. They found that the hBN suppressed superconductivity up to half a micrometre away, a distance ten times the width of the hBN flake itself.
A new milestone for material design
Historically, modifying a material required an external force, such as a mechanical push or a laser pulse. These changes are often short-lived. By using vacuum fluctuations, researchers can create more persistent modifications.
The thickness of the hBN layers can be adjusted to tune these vibrations, potentially allowing scientists to turn superconductivity on or off at will. This “tuning knob” is not limited to superconductors; it could be applied to magnets and ferroelectric materials. The study marks a proof of concept for integrating quantum cavity effects directly into future material designs, paving the way for a new era of quantum-engineered electronics.
