A report by the U.S. Defense Science Council cast doubt on claims that quantum radar would greatly enhance the military’s detection capabilities.
A top independent scientific advisory board to the U.S. Department of Defense (DOD) has thrown cold water on many recent predictions that quantum radar will not achieve new levels of detection far beyond conventional radar systems. But most damning of all, the US Defense Science Board (DSB) concluded that quantum radar technology “will not provide the Department of Defense with an upgrade capability.”
The DSB’s conclusions are cited in a May 2021 report by the Congressional Research Service (CRS). The report, “Introduction to Defense: Quantum Technologies,” outlines the ongoing quantum science research in the U.S. military. In addition to the bad news for quantum radar research, the report points to still promising applications for quantum science, including quantum sensing, quantum computers, and quantum communications.
Chinese Internet: Prototype of alleged Chinese quantum radar shown in 2018
In 2019, the DSB released a non-confidential abstract of its limited distribution report, “Applications of Quantum Technologies.” In his summary, DSB Director Craig Fields wrote that quantum technologies “show great potential to enhance or disrupt current combat capabilities” and that the Department of Defense “maintains a leading edge in understanding the advancements in these technologies.” “It’s crucial. In addition to concluding that quantum radar will not provide the U.S. military with any upgraded sensing capabilities, the report draws a number of other conclusions about quantum sensing:
Quantum science defines how the physical universe works at the subatomic level. Essentially, it’s a way of describing how the particles that make up an atom work and interact. In theory at least, quantum radar differs from other radar systems in that it uses entangled photons rather than reflected radio waves to detect targets. That is, quantum radar relies on a phenomenon called “quantum entanglement,” in which these subatomic particles are effectively linked together in pairs based on quantum properties. This seems to hold true regardless of distance, which could allow for very fast interactions between entangled particles, even if they are very far apart.
When a property of the entangled particles changes, the paired particles also change accordingly. For example, if one particle in an entangled pair has an upward spin, the other must have a downward spin. Therefore, related theories suggest that when one entangled particle emitted by quantum radar encounters a target, the other entangled particle should respond immediately accordingly, allowing for more precise and faster detection of the target. For example, if entangled particles emitted by quantum radar encounter an airplane, their entangled pair should respond immediately.
As with any emerging technology that has the potential to lead to revolutionary military applications, there are questions about adversary capabilities when it comes to quantum technology. The authors of the CRS report specifically asked “How mature are U.S. competitors’ efforts to develop military applications of quantum technology?” and “To what extent, if any, such efforts would threaten advanced U.S. military capabilities such as submarines and stealth? airplane?”
Considering the several quantum radar-related announcements made over the past few years, these issues have been on the radar for a while. MIT reported in 2019 that quantum radar had been demonstrated for the first time in Austria, but before that, China announced in 2018 that it had developed a quantum radar system that could detect even the most powerful stealth platforms , thus making headlines. That same year, Canada began funding a quantum radar project. Earlier reports said China was developing satellites based on similar concepts that it claimed could render stealth technology obsolete. Similar claims are often made about new radar technology, but so far they have been mostly exaggerated.
By the way, this is what quantum radar looks like. Can anyone translate the brochure? #Zhuhai pic.twitter.com/e47m03hXFv
— Steve Trimble (@TheDEWLine) November 5, 2018
While the recent DSB report may cast doubt on the future of quantum radar to enhance the U.S. military’s tracking and detection capabilities, the U.S. Department of Defense still has many opportunities to use the latest quantum information science to improve other capabilities and systems. The Office of the Secretary of Defense did not provide exact figures in its latest budget request for all quantum science research in fiscal year 2022, but the DSB report estimates that the Pentagon has allocated more than $688 million for quantum technology research in the current fiscal cycle.
In the Pentagon’s proposed FY 2022 budget, the Office of the Secretary of Defense (OSD) requested an additional $29 million for “quantum information science technology innovation” through its Technology Innovation Program element, although work on quantum radar is not among the programs listed.
In 2020, the U.S. Navy designated the Naval Research Laboratory as its quantum information research center, while the U.S. Air Force Research Laboratory has its own quantum science research program. The U.S. Department of Energy is also investing heavily in quantum information science. The DSB has previously noted that the DoD’s interest in quantum technologies “far exceeds commercial interests” and that “the department will need to be a key investor in bringing these technologies to a deployable-ready level,” and suggested working with academia to advance its research.
DSB finds there is still hope for quantum sensing, quantum computing and quantum communications, areas that the OSD outlined in its fiscal 2022 budget request. Quantum sensing involves using the properties of entanglement to develop sensors that are far more sensitive than conventional systems. Applications include more accurate Global Positioning System (GPS) systems; making more sensitive magnetic sensors for maritime surveillance; detecting underground structures and nuclear materials; and more.
At the same time, quantum computing can provide exponentially higher processing speeds than those available today. AI and machine learning are top priorities for quantum computing research, with the DSB recommending in 2019 that the Department of Defense “must monitor and understand technological advances in quantum computing both domestically and internationally in order to rapidly capitalize on emerging advances.” Integrated into DoD’s front-to-back operations, quantum computing will clearly become a larger research focus.
Finally, quantum communications could one day exploit entanglement to create point-to-point encrypted communications that could be protected to the point of being virtually immune to eavesdropping or cyberattacks. Last year, however, the U.S. Department of Defense’s undersecretary of defense for research and engineering noted that all three areas of research still have long-term prospects and that the Defense Department should maintain realistic projections about its timelines.
Still, as recently as February 2021, the Office of the Under Secretary of Defense for Research and Engineering boasted that its research into quantum science could enable new levels of aircraft or missile tracking. Now that the report claims that quantum radar offers no enhanced capabilities, the DoD may shift its quantum science research focus to other applications.