Cobalt could offer a cheaper route to exotic quantum materials

[Rabbit21]

SciTechDaily reports on research from the University of Osaka suggesting that cobalt, a common and relatively cheap metal, could replace rare metals in some exotic quantum materials. The team, led by Hao-Bo Li with senior author Hidekazu Tanaka, published the work in Physical Review Materials. They created a thin film of sodium antimonate doped with cobalt. The surprise was that the cobalt atoms arranged themselves into honeycomb structures on their own

Honeycomb arrangements of magnetic atoms are important because of something called Kitaev materials. These are predicted to host quantum spin liquids, an exotic state where magnetic spins never settle into a regular pattern even at very low temperatures. Some theories suggest they could be used for robust, topological quantum computing. Until now, the best candidates relied on expensive rare metals like ruthenium and iridium. Iridium is one of the rarest elements in the Earth's crust

The cobalt film showed ferromagnetic behaviour near 88 Kelvin and magnetic interactions relevant to Kitaev type systems. Li pointed out that cobalt is relatively cheap, widely available and already used in semiconductor manufacturing. Tanaka said the cobalt honeycombs appear to form naturally, without any special coaxing. Self assembly is a big deal, because it is far easier than placing atoms precisely by hand

Being a thin film is also useful. Thin films can be grown with the same kind of equipment used in the chip industry, which could make it easier to integrate them into devices. Iridium in particular is extremely rare and expensive, so finding a cheaper substitute could open the field to more labs and eventually to products. Whether the cobalt version shows true quantum spin liquid behaviour still needs more research. Peer review of follow up work will matter here

It is early days, and ferromagnetism is not the same as a spin liquid, so this is a promising first step rather than a breakthrough device. Still, materials science quietly underpins everything in quantum technology. Does anyone here follow Kitaev materials? And how important is cost in deciding which quantum technologies eventually win?

Common Metal Could Unlock a Cheaper Path to Quantum Materialsscitechdaily.com

[Glenn82]

Iridium costs a fortune and is incredibly scarce. Any technology that depends on it will struggle to scale

Cobalt has its own supply issues because of mining practices, but it is far more plentiful. That makes a big difference for research budgets

[VelvetFalcon]

Thin films being compatible with chip manufacturing is the practical win. Bulk crystals are lovely for physics experiments but hard to build devices from. Device engineers think in films, not crystals. Fabs already handle thin film deposition at huge scale

That makes the route to real devices much shorter. It is a practical advantage people often overlook

[Cantona]

Self assembling honeycombs is the most exciting part. Getting atoms to arrange themselves saves enormous effort. Nature doing the hard work for you is always welcome. Fabrication costs could fall dramatically if this works reliably

[Quiet Hermit]

Cost decides almost everything in the end. Plenty of brilliant technologies lost to cheaper ones that were good enough

Silicon beat germanium partly for that reason. History tends to repeat

[Grim Tracey]

Kitaev spin liquids have been a holy grail for years. Lots of candidate materials, very few convincing results. A new family to study is welcome. Ruthenium chloride got everyone excited a few years back, then the evidence became murky. Healthy scepticism is wise