# PPPL physicists propose modeling diamond qubit defects as molecules to cut computing cost

- Published: 2026-11-14 12:25 UTC
- Section: Digital & Computing › Quantum technology
- Tags: Princeton Plasma Physics Laboratory, diamond qubits, diamond defects, quantum sensors, Mark Martirez, ACS Central Science, molecular modeling, room-temperature qubits
- URL: https://realtech.media/news/rt-2ceab9ef84f5337ecb79389f_pppl_physicists_propose/

**The method treats 16–30 atoms around a defect as a molecule, which, according to the author, cuts computing cost several-fold. It is meant to speed up the search for qubit candidates.**

![PPPL physicists propose modeling diamond qubit defects as molecules to cut computing cost](https://realtech.media/media/2026/11/ed731cccd5f8edbf.jpg)
*pravda.ru*

Researchers at the Princeton Plasma Physics Laboratory (PPPL) have proposed a way to speed up the search for building blocks of quantum computers and ultrasensitive sensors, according to pravda.ru. They apply to diamond qubits methods that chemists have used for decades to model molecules. The results are published in ACS Central Science. [1]

## Diamond defects as qubits

A qubit is the basic unit of information in a quantum computer. Unlike a bit, which is either 0 or 1, a qubit can be in both states at once. Most current quantum systems are finicky and work only at extremely low temperatures, whereas diamond retains its properties at room temperature. [1]

For quantum tasks, a flawless crystal is not what is needed; a diamond with defects is. If a carbon atom is replaced with another element, or a vacancy is created, a kind of trap for electrons forms around the disruption and becomes the qubit. [1] The difficulty is that calculating how such a defect behaves at the quantum level requires enormous computing power. [1]

## A molecule instead of a lattice

PPPL research staff member Mark Martirez proposed not computing the whole diamond lattice but treating the region around the defect, just 16 to 30 atoms, as an ordinary molecule. "Because we analyze the qubit as a molecule, the computational cost drops severalfold," Martirez says. [1] The method lets researchers quickly estimate how different defects, for example those with boron or oxygen, respond to laser radiation and microwave pulses. [1]

Different defects interact with light differently. Nitrogen defects usually emit red light, oxygen defects emit blue, and boron defects emit ultraviolet. [1] This makes it possible to combine different qubit types in one device and address one group of qubits with a laser of a particular color without affecting the others, which simplifies control of future quantum processors, the report says. [1]

Martirez notes that chemists have built up an intuitive understanding of such systems over decades, which suits the study of defects in solids. In his words, physicists and chemists need to work together to bring quantum computing closer. [1]

## Sources

1. [pravda.ru](https://www.pravda.ru/news/science/2442580-diamond-quantum-computing-breakthrough)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-2ceab9ef84f5337ecb79389f_pppl_physicists_propose/