- Publication Date: Feb. 29, 2024
- Vol. 6, Issue 1, 010101 (2024)
- Publication Date: Jan. 19, 2024
- Vol. 6, Issue 1, 010501 (2024)
- Publication Date: Feb. 15, 2024
- Vol. 6, Issue 1, 010502 (2024)
- Publication Date: Feb. 28, 2024
- Vol. 6, Issue 1, 010503 (2024)
- Publication Date: Jan. 08, 2024
- Vol. 6, Issue 1, 014001 (2024)
- Publication Date: Feb. 09, 2024
- Vol. 6, Issue 1, 014002 (2024)
Being invisible ad libitum has long captivated the popular imagination, particularly in terms of safeguarding modern high-end instruments from potential threats. Decades ago, the advent of metamaterials and transformation optics sparked considerable interest in invisibility cloaks, which have been mainly demonstrated in ground and waveguide modalities. However, an omnidirectional flying cloak has not been achieved, primarily due to the challenges associated with dynamic synthesis of metasurface dispersion. We demonstrate an autonomous aeroamphibious invisibility cloak that incorporates a suite of perception, decision, and execution modules, capable of maintaining invisibility amidst kaleidoscopic backgrounds and neutralizing external stimuli. The physical breakthrough lies in the spatiotemporal modulation imparted on tunable metasurfaces to sculpt the scattering field in both space and frequency domains. To intelligently control the spatiotemporal metasurfaces, we introduce a stochastic-evolution learning that automatically aligns with the optimal solution through maximum probabilistic inference. In a fully self-driving experiment, we implement this concept on an unmanned drone and showcase adaptive invisibility in three canonical landscapes—sea, land, and air—with a similarity rate of up to 95%. Our work extends the family of invisibility cloaks to flying modality and inspires other research on material discoveries and homeostatic meta-devices.
.- Publication Date: Jan. 12, 2024
- Vol. 6, Issue 1, 016001 (2024)
- Publication Date: Jan. 25, 2024
- Vol. 6, Issue 1, 016002 (2024)
Fluorescence confocal laser-scanning microscopy (LSM) is one of the most popular tools for life science research. This popularity is expected to grow thanks to single-photon array detectors tailored for LSM. These detectors offer unique single-photon spatiotemporal information, opening new perspectives for gentle and quantitative superresolution imaging. However, a flawless recording of this information poses significant challenges for the microscope data acquisition (DAQ) system. We present a DAQ module based on the digital frequency domain principle, able to record essential spatial and temporal features of photons. We use this module to extend the capabilities of established imaging techniques based on single-photon avalanche diode (SPAD) array detectors, such as fluorescence lifetime image scanning microscopy. Furthermore, we use the module to introduce a robust multispecies approach encoding the fluorophore excitation spectra in the time domain. Finally, we combine time-resolved stimulated emission depletion microscopy with image scanning microscopy, boosting spatial resolution. Our results demonstrate how a conventional fluorescence laser scanning microscope can transform into a simple, information-rich, superresolved imaging system with the simple addition of a SPAD array detector with a tailored data acquisition system. We expected a blooming of advanced single-photon imaging techniques, which effectively harness all the sample information encoded in each photon.
.- Publication Date: Jan. 27, 2024
- Vol. 6, Issue 1, 016003 (2024)
Efficient and precise photon-number-resolving detectors are essential for optical quantum information science. Despite this, very few detectors have been able to distinguish photon numbers with both high fidelity and a large dynamic range, all while maintaining high speed and high timing precision. Superconducting nanostrip-based detectors excel at counting single photons efficiently and rapidly, but face challenges in balancing dynamic range and fidelity. Here, we have pioneered the demonstration of 10 true photon-number resolution using a superconducting microstrip detector, with readout fidelity reaching an impressive 98% and 90% for 4-photon and 6-photon events, respectively. Furthermore, our proposed dual-channel timing setup drastically reduces the amount of data acquisition by 3 orders of magnitude, allowing for real-time photon-number readout. We then demonstrate the utility of our scheme by implementing a quantum random-number generator based on sampling the parity of a coherent state, which guarantees inherent unbiasedness, robustness against experimental imperfections and environmental noise, as well as invulnerability to eavesdropping. Our solution boasts high fidelity, a large dynamic range, and real-time characterization for photon-number resolution and simplicity with respect to device structure, fabrication, and readout, which may provide a promising avenue towards optical quantum information science.
.- Publication Date: Feb. 02, 2024
- Vol. 6, Issue 1, 016004 (2024)
- Publication Date: Feb. 02, 2024
- Vol. 6, Issue 1, 016005 (2024)
- Publication Date: Feb. 06, 2024
- Vol. 6, Issue 1, 016006 (2024)
About the Cover
Featured on the cover is a schematic of a system utilizing metasurface-based optical modulation and computation. It modulates high-dimensional optical signals, encoding target information for tailored imaging tasks. Combined with co-optimized computational reconstruction, this approach ensures the high-quality recovery of diverse data types – hyperspectral, full-Stokes polarization, wavefront phase, or depth – depending on the specific imaging challenge.