TAU Experimenting with Modern Alchemy: Can Copper Be Turned into Gold?

Photo Credit: Joseph Wright of Derby / Derby Museum and Art Gallery

The Alchemist in Search of the Philosophers Stone (1771). Oil on canvas.

Can copper be transformed into gold? For centuries, alchemists chased this dream, unaware that achieving such a change requires a nuclear reaction. In contrast, graphite—the material in pencil tips—and diamond are both composed purely of carbon atoms; their difference lies in the atomic arrangement. Converting graphite into diamond demands extreme temperatures and pressures to break and reform chemical bonds, making it impractical.

However, a more viable transformation, according to Prof. Moshe Ben Shalom, head of the Quantum Layered Matter Group at Tel Aviv University, involves reconfiguring graphite’s atomic layers by subtly shifting them against weak van der Waals forces.

Named after Dutch physicist Johannes Diderik van der Waals (1837 – 1923), the van der Waals force is a distance-dependent interaction between atoms or molecules. Unlike ionic or covalent bonds, these forces do not arise from chemical electronic bonding. Instead, they are relatively weak attractions that can be easily disrupted. Additionally, the van der Waals force diminishes rapidly as the distance between interacting molecules increases.

The TAU research, conducted by Prof. Ben Shalom alongside PhD students Maayan Vizner Stern and Simon Salleh Atri from Tel Aviv University’s Raymond & Beverly Sackler School of Physics & Astronomy, was recently published in Nature Review Physics (Sliding van der Waals polytypes).

While this method won’t produce diamonds, if the switching process is fast and efficient, it could function as a tiny electronic memory unit. In that case, these newly engineered “polytype” materials might surpass both diamonds and gold in value.

PhD student Maayan Vizner Stern explains: “Like graphite, many naturally occurring materials consist of weakly bonded layers. Each layer acts like a LEGO brick—while breaking a single brick is difficult, separating and reconnecting two bricks is relatively simple. Similarly, in layered materials, atoms prefer specific stacking positions, aligning perfectly with those in neighboring layers. Sliding between these positions occurs in tiny, discrete jumps—just an atomic distance at a time.”

PhD student Simon Salleh Atri elaborates: “We are developing new techniques to shift these layers into different arrangements and study the resulting materials. By applying an electric field or mechanical pressure, we can move the layers into various stable configurations. Since these layers remain in their final position even after the external force is removed, they can store information, effectively serving as tiny memory units.”

Their team has also explored how the number of layers affects material properties. For instance, a three-layer structure with two types of atoms can form six distinct stable materials, each with unique internal polarizations. With five layers, this number rises to 45 different possible structures. By switching between these configurations, researchers can control electrical, magnetic, and optical properties. Even graphite, composed solely of carbon, can reorganize into six different crystalline forms, each exhibiting distinct electrical conductivities, infrared responses, magnetizations, and superconducting properties.

The main challenge lies in maintaining material stability while enabling controlled structural transitions. Their recent perspective paper summarizes ongoing studies and proposes new methods to refine this “Slidetronics” switching mechanism, opening the door to groundbreaking applications in electronics, computing, and beyond.

With continued research, these sliding materials could revolutionize technology, offering faster, more efficient memory storage and unprecedented control over material properties. The ability to manipulate atomic layers with precision is unlocking a new era in material science—where the most valuable discoveries may not come from creating gold, but from harnessing the hidden potential of everyday elements.