This page belongs to: Action Plan for Critical Technologies

Quantum communications (incl. quantum key distribution)

Devices and systems that communicate quantum information at a distance, including cryptographic keys. Applications for quantum communications include transferring information between quantum computers and sharing cryptographic keys (which are like secret passwords) between distant people in a way that means it is impossible for anyone else to copy.

Key sectors

  • Defence Industry
  • Intelligence
  • Communications
  • Banking & Finance

Estimated impact on national interest

Economic Prosperity - Med
National Security - Med

Key Australian Government actions


  • Quantum Technology Roadmap
  • Australian Cyber Security Growth Network
  • The ARC Centre of Excellence for Quantum Computation and Communication Technology
  • Next Generation Technologies Fund
  • Silicon Quantum Computing
  • Digital economy and technology policy


  • Quantum Technology Roadmap
  • Australian Cyber Security Growth Network
  • The ARC Centre of Excellence for Quantum Computation and Communication Technology
  • Next Generation Technologies Fund
  • Silicon Quantum Computing
  • Digital economy and technology policy

Example outcomes

  • Communicating quantum information between remote sites
  • Secure cryptographic key exchange between strangers

Underpinning science

ANZ Standard Research Classification Category

  • Applied mathematics
  • Mathematical physics
  • Numerical and computational mathematics
  • Software engineering
  • Data management and data science
  • Theory of computation
  • Electronics, sensors and digital hardware
  • Mechanical engineering
  • Electrical engineering
  • Optical physics
  • Quantum physics
  • Electronics, sensors and digital hardware

Example applications

Readiness Level – Now

  • Technical demonstration of quantum key distribution between remote sites

Readiness Level – 2–5 years

  • Technical demonstration of quantum key distribution between remote sites

Readiness Level – Beyond 5 years

  • Large-scale testing of a secure quantum key distribution network
  • Quantum networks to enhance the computing capability of quantum computers
  • Blind quantum computing which will allow users across the globe to securely and remotely access quantum computers to run calculations without disclosing the calculations or results

Australia's place in the world

China has the highest research impact in this area and has 4 of the global top 10 institutions, well ahead of the United States, which is ranked 2nd and only has 1 institute in the international top 10 institutions. Australia ranks 7th globally for research impact in this field, led by the University of Technology Sydney, which is ranked 6th internationally. The United States leads venture capital (VC) investment in this area, followed by the United Kingdom and Canada; Australia has the 9th highest VC investment. China has the greatest number of patents in this area, with more than three times as many patents as the United States, in second place; Australia ranks 23rd with 6 patents.

Australia ranks highly in this field with significant expertise in the development of quantum communications technology, and was an early leader in the development and commercialisation of quantum technologies for secure communication. The Australian Research Council Centres of Excellence program, university, and private sector investment facilitate much of Australia’s research on quantum. The Australian Government’s investment in overall quantum technology research, including quantum communications, was AU$195 million in 2020.

Opportunities and risks

Quantum communications promises to enable the transfer of information in quantum states, rather than in the digital form of most modern communications technologies. This will enable communications between quantum computers and other quantum systems, which can save time and fidelity by communicating quantum information directly, rather than by conversion to a digital form. Quantum communications also power quantum key distribution (QKD), which exploits the inherent properties of quantum mechanics to detect efforts to intercept or eavesdrop on people exchanging cryptographic (with users reverting to non-quantum communications technologies once the keys are exchanged).

Noting the importance of quantum technologies in global political and security considerations, Australia’s increased quantum capabilities and research may also bring with it security risks stemming from geopolitical importance of quantum technologies. Risks could include foreign interference and the unwanted transfer of quantum research and technologies, IP theft, and espionage on Australia’s defence quantum communications and technological capabilities. It has been suggested that quantum communications may introduce new potential avenues for attack, such as physically interrupting satellite-based quantum key distribution using high-power ground-based lasers.

It is likely that impractical and expensive hardware and limited realworld use cases may make quantum key distribution unsuitable for future challenges, and that it will be superseded by post-quantum cryptography before it is established.

Research impact (RI)

China leads research impact in this area, with Australia ranked 7th. Total volume of published research has increased at around 10% p.a. over the 5 year period 2016–2020, with 28% of research involving international collaboration.

  1. China - 13691
  2. USA - 9743
  3. UK - 6436
  4. Germany - 4565
  5. Canada - 3631
  1. Australia - 2569

The research impact provides an indication of the productivity of a country or institution. Here, productivity was assumed to be represented by the volume of publications (i.e. scholarly output) as an indicator of the resources & facilities, and the level of interest in the publications as an indicator of quality.

VC investment

The United States has the highest venture capital (VC) investment for quantum communications, with Australia ranked 9th. Investment in this area has been increasing at around 26% p.a.

  1. USA
  2. UK
  3. Canada
  4. China
  5. Japan
  1. Australia

Data from Crunchbase. The Crunchbase database provides a partial view of the global VC landscape. However the quantity, quality and richness of the data are considered to be statistically significant, and indicative of global trends.

Patents - international

The highest number of patents for this technology were filed by Chinese applicants or inventors, more than three times the number of the United States. Overall patent applications have been increasing at 30% annually since 2015

  1. China - 2139
  2. USA - 663
  3. R. of Korea - 189
  4. Taiwan - 122
  5. Japan - 97
  1. Australia - 6

Research institutions - international

China has 4 of the top 10 research institutions, including the top three. There are a number of European institutes in the top 10.

Rank Top International Institution Research Impact
1 University of Science and Technology of China | China 4287
2 Chinese Academy of Sciences | China 3966
3 Tsinghua University | China 1758
4 French National Centre for Scientific Research (CNRS) | France 1546
5 Delft University of Technology | Netherlands 1462
6 University of Technology Sydney | Australia 1432
7 Austrian Academy of Sciences | Austria 1408
8 Massachusetts Institute of Technology | United States 1190
9 Peking University | China 1130
10 University of Waterloo | Canada 1126

Research institutions - Australia

Within Australia, the University of Technology Sydney has the highest research metric, which places it 6th compared to the top international institutions. All of the top 6 Australian universities are ranked in the top 50 international institutions.

Rank Top Australian Institution Research Impact
1 University of Technology Sydney 1432
2 Australian National University 924
3 Royal Melbourne Institute of Technology University 844
4 University of New South Wales 715
5 Griffith University Queensland 694
6 University of Melbourne 662
7 University of Sydney 492
8 University of Queensland 183
9 Macquarie University 164
10 University of Western Australia 129

Patents - Australia

All Australian patents in this area are held by private citizens.