Efficient quantum private queries based on quantum key distribution with pulse-position modulation

Abstract

Up to now, there are only a few studies on the application of pulse position modulation (PPM) and orbital angular momentum (OAM) in measurement-device-independent (MDI) quantum private queries (QPQ) protocols. Given this, we design a QPQ protocol based on PPM-OAM and MDI-QKD (quantum key distribution), i.e. PPM-OAM-MDI-QPQ protocol, which avoids the dependence of the basis besides inheriting the advantages of MDI-QPQ. Our PPM-OAM-MDI-QPQ protocol can achieve longer-distance QPQ and speed up private queries. Moreover, our PPM-OAM-MDI-QPQ protocol can eliminate the basis-dependent flaw and demonstrate a useful technique for high-rate satellite-based QPQ. Meanwhile, our protocol applies quantum memory to achieve the function of a quantum repeater, achieving much longer-distance QPQ.

Fluorescent small organic probes for biosensing

“…35 However, the extent of photobleaching can be minimised by use of higher pulse repetition rates in preference to a continuous laser source. 36 In this perspective, we will highlight the features of fluorescent probes that use a variety of different fluorescence mechanisms, with a focus on those that have shown promise in the realms of biological sensing and imaging. Moreover, we will highlight how fluorescent probes with optimized optical properties are powerful tools for biological research.…”

“… 35 However, the extent of photobleaching can be minimised by use of higher pulse repetition rates in preference to a continuous laser source. 36 …”