Quantum computing startup Diraq has expanded its Series 2-A funding round by raising an additional $7 million.

The Sydney-based company originally raised $15 million in a February funding round. This extended round saw contributions from Main Sequence, Taronga Ventures, Uniseed, UniSuper, Co:Act Capital, and UNSW Sydney.

Founded in 2022, Diraq builds quantum processors using silicon quantum dot technology. Quantum dots, also known as semiconductor nanocrystals, have differing optical and electronic properties from larger semiconductor particles, which gives them the ability to transport electrons and emit light of various colors when exposed to UV light.

The technology has a number of potential applications, including use in solar cells, fluorescent biological labeling, displays, lighting, and medical imaging.

Diraq is also aiming to build a full-stack quantum computer that moves the industry away from what it describes as "large, error-ridden systems" and towards fault-tolerant computing.

To date, Diraq has raised $120 million, including research funding from Australian and US government programs.

According to Australia’s national science agency, CSIRO (Commonwealth Scientific and Industrial Research Organisation), the domestic quantum computing market has an estimated annual revenue of AU$2.5 billion ($1.6bn), with the potential to create 10,000 new jobs in Australia by 2040.