Boron-doped diamonds show promising properties for quantum
Researchers from Case Western Reserve University and the University of Illinois Urbana-Champaign have discovered new properties in boron-doped diamonds (BDDs) that have the potential to enhance quantum processing capabilities.
Diamond is one of the most critical materials we know of owing to its unmatched hardness and transparency as well as its ability to be engineered in many ways. It is through this engineering that diamond has emerged as a key material for the future of high-power electronics and next-generation quantum optics.
Diamonds are composed of carbon crystals which can be synthesised with small amounts of boron which lies adjacent to carbon on the periodic table. Boron has one less electron when compared to carbon, which means that it can accept electrons. When synthesised into diamond, boron acts as a periodic electronic ‘hole’ that increases its ability to conduct current.
By doping diamond with boron to produce BDDs, diamonds can become as electrically conductive as the popular metals we use in everyday life. Recent research, published in Nature Communications, has shown that BBDs could pave the way for new types of quantum optical devices.
Plasmons
Researchers have discovered that these BDDs exhibit waves of electronics that move when light contacts them, known as plasmons. This property allows electric fields to be controlled and enhanced on a nanometre scale.
Operating at this scale is critical to many different applications such as biosensors, optical devices, solar cells, and of course within quantum devices. It had been previously believed that BDDs were only capable of electrical conductivity which enabled superconductivity, not that they featured plasmonic properties – now this is proven to be false. Unlike the metals or other doped materials traditionally used for semiconductors, BDDs maintain the transparency that diamond is known for.
Commenting on the findings, Giuseppe Strangi, Professor of Physics at Case Western Reserve, said: “Diamond continues to shine, both literally and as a beacon for scientific and technological innovation. As we step further into the era of quantum computing and communication, discoveries like this bring us closer to harnessing the full potential of materials at their most fundamental level.”
Mohan Sankaran, Professor of Nuclear, Plasma and Radiological Engineering at Illinois Grainger College of Engineering, added: "Understanding how doping affects the optical response of semiconductors like diamond changes our understanding of these materials."
Why it matters
Thanks to the unique properties of BBDs, the material is also non-reactive and biologically compatible. This unlocks the material to being applied across a wide range of different industries where other materials would not be compatible. Medical applications are at the top of this list, from high-sensitivity biochips or cutting-edge molecular sensors. This could unlock a whole new generation of this technology, granting people access to non-invasive, highly accurate medical sensing technologies that utilise quantum level sensing.
This is only the beginning of what might be achieved utilising such a material, with quantum sensing being highly anticipated in chemical, environmental, magnetic field sensing applications as well as in future automation endeavours. This material might also see use in future quantum computing applications where diamonds are gaining traction.