An innovative breakthrough in quantum technology has emerged with the development of a new quantum microscope prototype by Australian researchers from the University of Technology Sydney and RMIT University, led by Professor Igor Aharonovich and Dr. Jean-Philippe Tetienne. This advancement represents a significant leap in microscopy capabilities, enabling the visualization of electric currents, detection of fluctuating magnetic fields, and observation of individual molecules on surfaces.
The quantum microscope’s core technology relies on atomic impurities that emit light when exposed to laser illumination. This emitted light can be directly correlated to various physical properties, including magnetic fields, electric fields, and the chemical environment near the defect. What sets this prototype apart is its use of hexagonal boron nitride (hBN), an atomically thin material, rather than the bulky crystals typically employed in quantum sensing.
The use of hBN, a van der Waals material composed of strongly bonded two-dimensional layers, provides several crucial advantages. Its extremely thin nature allows it to conform to irregular surfaces, enabling high-resolution sensitivity. This characteristic overcomes a significant limitation in traditional quantum microscopy, where spatial resolution and application flexibility were constrained by the interfacing issues associated with bulky three-dimensional sensors.
To demonstrate the prototype’s capabilities, the research team conducted quantum sensing experiments on CrTe2, a van der Waals ferromagnet with a critical temperature slightly above room temperature. The results were groundbreaking: the hBN-based quantum microscope successfully imaged magnetic domains of the ferromagnet under ambient conditions, with nanoscale proximity to the sensor—an achievement previously considered impossible.
Furthermore, the microscope demonstrated an unexpected capability for dual sensing. The unique properties of hBN defects allowed simultaneous recording of temperature maps alongside magnetic measurements. This dual-sensing ability was discovered when researchers noticed that the material’s thinness prevented heat dissipation, maintaining the same temperature distribution as if the sensor were absent.
The implications of this new quantum microscope extend far beyond the laboratory. According to Dr. Mehran Kianinia, a senior researcher at UTS, the technology offers significant potential across various fields. The microscope can operate at room temperature, provide simultaneous data on temperature, electric, and magnetic fields, and integrate seamlessly into nanoscale devices. Its durability is enhanced by hBN’s rigid structure, allowing it to withstand harsh environments.
Looking ahead, the technology shows promise for several high-impact applications. These include high-resolution magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR), which could advance our understanding of chemical reactions and molecular structures. The microscope’s capabilities also make it valuable for space exploration, defense applications, and agricultural developments where remote sensing and imaging play crucial roles.
This advancement represents a significant step forward in quantum technology applications, offering new possibilities for scientific research and practical applications. The team’s findings, published in Nature Physics, demonstrate how quantum microscopy can evolve beyond traditional limitations to provide more detailed and comprehensive insights into the behavior of materials at the atomic and molecular level. The work was led by PhD students Alex Healey and Sam Scholten from the University of Melbourne, along with early career researcher Tieshan Yang from UTS, showcasing the collaborative nature of this breakthrough in quantum microscopy.
Reference: A. J. Healey, S. C. Scholten, T. Yang, J. A. Scott, G. J. Abrahams, I. O. Robertson, X. F. Hou, Y. F. Guo, S. Rahman, Y. Lu, M. Kianinia, I. Aharonovich, J.-P. Tetienne. Quantum microscopy with van der Waals heterostructures. Nature Physics, 2022; DOI: 10.1038/s41567-022-01815-5