Scientists at the University of Southern California recently achieved a remarkable breakthrough in the more experimental realm of quantum sensing. Doctoral student Malida Hecht headed up this novel exploratory study, with senior author Eli Levenson-Falk. They have provided an intriguing approach that addresses the long-standing issue of decoherence, which disrupts quantum superpositions and impacts the accuracy of quantum measurements. The work, published as a rapid communication in the journal Nature Communications, is aimed at increasing the operational potential of quantum sensors. These sensors are the backbone for many applications ranging from medical imaging to navigation.
The interdisciplinary research team, which includes scholars from USC Dornsife College of Letters, Arts and Sciences and the USC Viterbi School of Engineering, achieved a critical milestone. They went on to successfully realize a new pre-determined coherence-stabilized protocol, which stabilizes a key resource property of quantum states. The researchers used this protocol to pretty amazing effect. They increased efficacy per measurement by a factor of 1.65 over the standard Ramsey interferometry approach. The theoretical analysis indicates that for certain systems, we might see improvements of up to 1.96 times.
Understanding Decoherence
Decoherence is still considered one of the biggest hurdles in quantum computing and sensing. Eli Levenson-Falk is an assistant professor at USC, splitting his time between teaching physics and astronomy, and electrical and computer engineering. He presented the larger societal impacts of this alarming trend.
“Decoherence causes the state of a quantum system to become randomly scrambled, erasing any quantum sensing signal.” – Eli Levenson-Falk
As a case study example, this paper presents an original technique to mitigate the impact of decoherence. It uses a generic protocol that works, by design, to maintain coherence over time. In their work, the researchers stabilized quantum states to achieve maximum sensitivity. This innovation advanced the field by allowing signals that would otherwise be lost in noise to be more easily detected.
Melida Hecht (NIST) illustrated the challenge of making quantum systems work operationally.
“Think of it as trying to hear a faint whisper in a noisy space.” – Malida Hecht
Her account underscores how crucial it is to make quantum measurements as unambiguous as possible in order to collect good data.
Implications for Quantum Sensing
The impact of this study goes beyond the hallways of academia, boosting the future of quantum sensing technologies. Levenson-Falk wanted to underscore that their results show the promise of these approaches has not yet been maximized.
“It also shows that we have not yet extracted all the possible information from these types of measurements. Even better sensing protocols are out there, and we could use them to make immediate real-world impacts.” – Eli Levenson-Falk
Hecht and her team have been at the forefront of the amazing advancements being made in quantum sensors. Through their work, they make way for thrilling advances in medical diagnostics and environmental monitoring.
The researchers’ protocol is more than just a theoretical breakthrough. It’s a very real leap closer to being able to achieve real world applications. By enhancing the ability to detect subtle changes in physical systems, this protocol could open doors to innovations that rely on precision measurements.
Future Directions
Looking forward, the research team aims to determine additional improvements that can be made to their protocol. The theoretical groundwork that Daniel Lidar and Kumar Saurav have established supports their efforts, offering a strong foundation for further breakthroughs. As they further their pilots and keep iterating on their approach, Hecht and Levenson-Falk are optimistic over the development of quantum sensing technology.
The entire team gets to work in figuring what coherence is, how it contributes to or destroys the effects we’re interested in on quantum systems. Because their aspirations are to stretch what’s possible. Even greater sensitivity is possible, and the potential to do so could change how scientists and engineers in many fields use quantum sensors in countless applications.