As the quantum technology develops, more new areas, although previously they were presented mainly in cryptography and calculations. Next in line are quantum sensors that will allow you to perform safe measurements at a distance without fear of interception or distortion.
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Safety during distance measurements is important for creating high -precision quantum radars, cosmic basing systems, monitoring the condition of patients at home and other areas, where both measurement accuracy and their protection are critical. Scientists from the British University of Sussex (University of Sussex) have been actively engaged in this topic.
Recently, a new article was published in the journal Physical Review a, in which researchers talked about possible schemes for the implementation of secure measurements using simplified quantum sensors. In the basic configuration, it is not even required to confuse cubes – everything is realized much easier, although the effect of confusion can significantly increase the accuracy of measurements.
The main idea of SQRS technology (safe quantum remote sensing) is that single photons are sent to the measurement point. They are delivered through open classic channels, for example, through a fiber or laser beam, if we are talking about transmission to a satellite. At the destination, photons acquire a phase shift in accordance with the measured data and then return to the sender through the same open channels.
In the proposed scheme, only the sender can get the result, since he owns complete information about the quantum states of the sent photons. The recipient at the measurement point will not be able to determine the value of the phase shift, since he does not have reference data for calculations. An attacker who managed to intercept such photons will also not be able to restore the transmitted message, since additional quantum uncertainty is introduced at the measurement stage (at the time of phase shift).
Scientists from China were able to improve the proposed technique. Their article, published on the Arxiv website, has not yet passed the review. Researchers from the University of Guangxi University showed that it is not necessary to use single photons to implement SQRS, which requires quite complicated equipment. In their work, they proved that you can do with a weak source of photons. Using the laws of statistics, such a source can be considered single -photon, adjusting the indicators using mathematical methods.
The proposal of Chinese researchers brings the practical implementation of safe quantum remote sensing, which can accelerate the development of quantum technologies.