Technologies made possible by Quantum science will help researchers better understand the natural world and harness quantum phenomena for the benefit of society. They will transform healthcare, transportation and communications, and improve resilience to cyber threats and climate catastrophes. For example, quantum magnetic field sensors will enable functional imaging of the brain; Quantum optical communication will enable encrypted communication; and quantum computers will facilitate the discovery of next-generation materials for photovoltaics and medicine.
Currently, these technologies rely on materials that are expensive and complicated to manufacture, and often require expensive and bulky cryogenic refrigeration to function. Such devices rely on precious raw materials such as liquid helium, which is becoming increasingly expensive as supply dwindles worldwide. 2023 will see a revolution in innovation in quantum materials that will transform quantum technologies. In addition to reducing environmental requirements, these materials enable room temperature operation and energy savings, are low cost, and have simple processing requirements. To optimize their quantum properties, research labs can manipulate the chemical structure and molecular packing. The good news is that physicists and engineers have been busy, and by 2023 these materials will be making their way out of the science labs and into the real world.
Recently, the UK Engineering and Physical Sciences Research Council, led by Imperial College London and the University of Manchester, announced a vision for innovation in materials for quantum technologies. The London Center for Nanotechnology – a coalition of hundreds of researchers from Imperial, King’s and University College London – has considerable experience in the simulation and characterization of quantum systems. The UK’s center for metrology – the National Physical Laboratory – has just opened the Quantum Metrology Institute, a multi-million pound facility dedicated to the characterisation, validation and commercialization of quantum technologies. Together, researchers and industry will herald a new era in pharmacy, cryptography and cybersecurity.
Qubits, the building blocks of quantum computers, rely on materials with quantum mechanical properties, such as electron spin, that can be manipulated. Once we can harness these properties, we can control them with light and magnetic fields and create quantum phenomena like entanglement and superposition. Superconducting qubits, the current state of the art in qubit technology, include Josephson junctions that function as superconductors (materials capable of conducting electricity without resistance) at extremely low temperatures (-273 °C). The stringent temperature and high frequency requirements mean that even the most fundamental aspects of these superconducting qubits – the dielectrics – are difficult to design. Currently, qubits include materials such as silicon nitride and silicon oxide, which have so many defects that the qubits themselves must be millimeters in size to store electric field energy, and crosstalk between adjacent qubits introduces significant noise. With these materials, it would be impossible to achieve the millions of qubits required for a practical quantum computer.
2023 will see more innovation in the design of materials for quantum technologies. Of the many great candidates that have been considered so far (e.g. diamonds with nitrogen vacancy defects, van der Waals/2D materials and high-temperature superconductors), I am most excited about using molecular materials. These materials are based on carbon-based organic semiconductors, which are an established class of materials for the scalable manufacture of consumer electronics (and have revolutionized the multi-billion-dollar OLED display industry). We can control their optical and electronic properties using chemistry, and the infrastructure around their development relies on well-established expertise.
For example, chiral molecular materials – molecules that exist as a pair of non-superimposable mirror images – will revolutionize quantum technologies. Thin, one-handed layers of these remarkably versatile molecules can be used to control the spin of electrons at room temperature. At the same time, the long spin coherence times and good thermal and chemical stability of metal phthalocyanines will lead them to be used to transport quantum information.
While 2023 will no doubt make headlines about the speed of quantum computing, materials scientists will study, discover and design the next generation of low-cost, highly efficient and sustainable quantum technologies.
https://www.wired.com/story/materials-computing-science/ New Materials Will Bring the Next Generation of Quantum Computers