Quantum sensors
PERSPECTIVES
availability constraints), or when quantum correlations offer unique capabilities( such as interaction-free detection), the quantum approach retains a decisive advantage that justifies the considerable efforts to prepare, control, and maintain quantum states. Furthermore, integrating quantum error correction would provide more robust quantum resources for sensors operating at the Heisenberg limit. With recent advances in research laboratories, the frontier of this competition is gradually shifting towards quantum solutions that clearly surpass their classical counterparts.
CONCLUSION Quantum sensors represent an exciting frontier at the intersection of fundamental physics and precision technologies. On one hand, the use of a system with discrete energy levels allows for developing absolute sensors, which therefore do not require calibration. This aspect is at the center of important efforts to determine more precisely the base units of the International System of Units. On the other hand, the laws of quantum mechanics allow for controlling correlations in such a way as to surpass the standard quantum limit, thus offering an enormous gain in sensitivity. The development of quantum sensors could consequently greatly impact fields as diverse as gravitational wave detection, medical imaging, inertial navigation, or geological prospecting. Recent advances in the generation and manipulation of non-classical quantum states, particularly in platforms such as circuit quantum electrodynamics, also suggest metrological applications operating at the fundamental limits allowed by physics. The main challenge, however, remains preserving the fragile quantum properties in the face of decoherence while maintaining the necessary interaction with the quantities to be measured. Meeting this challenge requires interdisciplinary approaches, combining quantum physics, materials science, and precision engineering.
REFERENCES
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