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The practical application of Na-superionic conductor structured materials is hindered by limited energy density and structure damage upon activating the third Na

Quantum-inspired imaging techniques have been proven to be effective for LiDAR with the advances of single photon detectors and computational algorithms. However, the quantum-limited performance is still far from its ultimate limit set by the quantum fluctuations of signal and noise photons. In this work, we propose and demonstrate LiDAR from the detection perspective for approaching quantum-limited performance. A photon-number-resolving detector is introduced to accurately reconstruct the echo signals in a wide photon-flux range and an active photon number filter is further developed to overcome the heavy background noise. The Fisher information of this LiDAR based on a coherent source is only 0.04 dB below the quantum limit in intensity detection when mean signal photon number is 10. An improvement of 41.17 dB in the signal-to-background ratio is achieved with the proposed LiDAR in daytime, and the accuracy of intensity estimation is consistent with the theoretical prediction, which helps to improve the quality of reconstructed images. This work provides a fundamental strategy for constructing a noise tolerant LiDAR approaching quantum-limited precision.

Precisely acquiring the timing information of individual X-ray photons is important in both fundamental research and practical applications. The timing precision of commonly-used X-ray single-photon detectors remains in the range of one hundred picoseconds to microseconds. In this work, we report on high-timing-precision detection of single X-ray photons through the fast transition to the normal state from the superconductive state of superconducting nanowires. We successfully demonstrate a free-running X-ray single-photon detector with a timing resolution of 20.1 ps made of 100-nm-thick niobium nitride film with an active area of 50 μ m by 50 μ m. By using a repeated differential timing measurement on two adjacent X-ray single-photon detectors, we demonstrate a precision of 0.87 ps in the arrival-time difference of X-ray photon measurements. Therefore, our work significantly enhances the timing precision in X-ray photon counting, opening a new niche for ultrafast X-ray photonics and many associated applications.

Electrochemical energy storage has experienced unprecedented advancements in recent years and extensive discussions and reviews on the progress of multivalent metal-ion batteries have been made mainly from the aspect of electrode materials, but relatively little work comprehensively discusses and provides an outlook on the development of electrolytes in these systems. Under this circumstance, this Review will initially introduce different types of electrolytes in current multivalent metal-ion batteries and explain the basic ion conduction mechanisms, preparation methods, and pros and cons. On this basis, we will discuss in detail the research and development of electrolytes for multivalent metal-ion batteries in recent years, and finally, critical challenges and prospects for the application of electrolytes in multivalent metal-ion batteries will be put forward.

A superconducting nanowire single-photon imager (SNSPI) uses a time-multiplexing method to reduce the readout complexity. However, due to the serial connection, the nanowire should be uniform so that a common bias can set all segments of the nanowire to their maximum detection efficiency, which becomes more challenging as the scalability (i.e., the length of the nanowire) increases. Here, we have developed a 64-pixel SNSPI based on amorphous Mo

A fan-out circuit is a basic block for scaling up digital circuits for overcoming the limited driving capability of a single logic gate. It is particularly important for superconducting digital circuits as the driving power is typically weak for having high energy efficiency. Here, we design and fabricate a fan-out circuit for a superconducting nanowire cryotron (nTron) digital circuit. A classic splitter tree architecture is adopted. To transmit switching signal and avoid crosstalk among nTrons, we introduced an “R–L–R” interface circuit. Experimentally, a two-stage splitter tree of a fan-out number of four was demonstrated. Correct operation was observed with a minimum bit error rate (BER) of 10−6. The bias margin was 10% at BER of 10−4. The average time jitter was 82 ps. Moreover, crosstalk was not observed. Based on these results, we envision that the fan-out circuit can be used in future development of superconducting-nanowire-based circuits.

Multilayer superconducting nanowire single-photon detectors (SNSPDs) have exhibited several advantages, such as increased detection efficiency, reduced polarization sensitivity, and scaling up to large arrays. However, monolithic fabrication of such multilayer devices is challenging. In this work, a hybrid integration method has been introduced by etching SNSPDs into the membrane microchips, followed by the pick and place transferring process. This method has been verified by stacking two SNSPDs orthogonally. Both detectors show near saturated detection efficiencies and low timing jitters. Furthermore, thermal coupling effects have been observed between the two SNSPDs. The photon detection pulses from either detector can trigger the other one almost deterministically with a latency of several nanoseconds. This method offers a flexible way to fabricate multilayer SNSPDs or integrate them with other heterogeneous devices.

A superconducting nanowire single-photon imager (SNSPI) uses a time-multiplexing method to reduce the readout complexity. However, due to the serial connection, the nanowire should be uniform so that a common bias can set all segments of the nanowire to their maximum detection efficiency, which becomes more challenging as the scalability (i.e., the length of the nanowire) increases. Here, we have developed a 64-pixel SNSPI based on amorphous Mo80Si20 film, which yielded a uniform nanowire and slow transmission line. Adjacent detectors were separated by delay lines, giving an imaging field of 270 µm × 240 µm. Benefiting from the high kinetic inductance of Mo80Si20 films, the delay line gave a phase velocity as low as 4.6 µm/ps. The positions of all pixels can be read out with a negligible electrical cross talk of 0.02% by using cryogenic amplifiers. The timing jitter was 100.8 ps. Saturated internal quantum efficiency was observed at a wavelength of 1550 nm. These results demonstrate that amorphous film is a promising material for achieving SNSPIs with large scalability and high efficiency.