Researchers have been able to accurately simulate two materials, hydrogen and iron, using algorithms and noise mitigation enabling them to run on today’s quantum computers. Most experiments for material discovery that have been run on today’s machines have been done on molecules. The new breakthrough, simulating an infinite iron lattice in two phases (where the molecules adopt different physical structures), is so complex it is considered to be inaccessible using classical computational methods.
One reason simulating periodic infinite iron crystals may prove valuable is that carbon is differently soluble in the different phases of iron, so this opens the way to discovering new types of steel through quantum computer modelling. Undiscovered characteristics of iron under high pressure may also hold secrets about the formation and internal nature of our own planet.
In summary:
CQC and partners have used newly created algorithms, alongside noise-mitigation software to simulate two periodic systems – a hydrogen chain, and an iron crystal on IBM’s Quantum Falcon Processors
They were able to simulate and output the structures of both the hydrogen chain, and iron crystal with a high-degree of accuracy
The team, led by Dr David Muñoz Ramo, has also confirmed a chemistry-specific noise mitigation method that exploits the symmetries of the system and does not consume quantum resources
Now that the efficacy of the algorithms, and their respective noise-mitigation software has proved successful, it represents a potential framework upon which quantum chemical calculations can be developed and advanced in line with the advancement of quantum hardware.
Why is this important?
One of the most promising suggested applications of quantum computing is solving complex chemistry problems not possible through the use of classic computing.
In areas like materials discovery, understanding biochemical reactions to build more efficient batteries, or learning more about high temperature superconductivity to help us create safer, more environmentally friendly materials, quantum computing promises to help answer many unresolved questions.
However, building a quantum computer that is large and stable enough to handle such complex problems, and do so at scale, is a significant scientific and economic challenge. The quantum bits (qubits) inside today’s quantum hardware are unstable and quickly become “noisy” as they lose coherence and stop being able to produce clear results when running an algorithm. These near-term devices are frequently referred to as Noisy Intermediate Scale Quantum (NISQ) devices.
Today’s breakthrough demonstrates that algorithms running on near-term devices can achieve meaningful discoveries.