Tiny imperfections in diamond crystal structures could unlock the next generation of quantum computers and ultra-sensitive sensors, according to research published in ACS Central Science.
Finding functional defects has traditionally required immense computational power to model large diamond lattices. Mark Martirez, a staff research scientist at the U.S. Department of Energy’s Princeton Plasma Physics Laboratory, solved this bottleneck by isolating a small cluster of 16 to 30 atoms surrounding a defect. Treating this tiny region as a separate molecule allows researchers to apply decades-old quantum chemistry methods without losing accuracy.
“Because we’re treating the qubits as molecules, the cost of calculating these defects is equivalent to the cost of just modeling a simple molecule,” Martirez told ScienceDaily. He added that the new approach “really opened the floodgates” for assessing potential qubits.
The computational breakthrough quickly revealed new defect candidates involving boron and oxygen. While nitrogen-vacancy centers typically emit red light under laser illumination, oxygen defects produce blue light, and boron defects emit ultraviolet light. These distinct optical frequencies could allow scientists to target specific qubit groups within a single device.
“One could imagine, then, combining different qubits of different responses, so you can basically probe one qubit but not the other,” Martirez said.
Martirez hopes the work encourages closer collaboration between solid-state physicists and chemists. A functional multi-qubit system could eventually model complex biological molecules and proteins with high precision, enriching fields like pharmaceutical science and materials research. “At this moment in time, there’s a great emphasis on building the first state-of-the-art qubit computer,” Martirez told ScienceDaily, adding that “it’s not just physicists who should be participating in this research.”
