Rewritable Photonic Integrated Circuit Canvas Based on Low-Loss Phase Change Material and Nanosecond Pulsed Lasers.

Programmable photonic integrated circuits (PICs) are an increasingly important platform in optical science and engineering. However, current programmable PICs are mostly formed through subtractive fabrication techniques, which limits the reconfigurability of the device and makes prototyping costly and time-consuming. A rewritable PIC architecture can circumvent these drawbacks, where PICs are repeatedly written and erased on a single PIC canvas.

Nonvolatile Phase-Only Transmissive Spatial Light Modulator with Electrical Addressability of Individual Pixels.

Active metasurfaces with tunable subwavelength-scale nanoscatterers are promising platforms for high-performance spatial light modulators (SLMs). Among the tuning methods, phase-change materials (PCMs) are attractive because of their nonvolatile, threshold-driven, and drastic optical modulation, rendering zero-static power, crosstalk immunity, and compact pixels. However, current electrically controlled PCM-based metasurfaces are limited to global amplitude modulation, which is insufficient for SLMs.

Erratum: Roadmap for phase change materials in photonics and beyond.

[This corrects the article DOI: 10.1016/j.isci.

Non-volatile electrically programmable integrated photonics with a 5-bit operation.

Scalable programmable photonic integrated circuits (PICs) can potentially transform the current state of classical and quantum optical information processing. However, traditional means of programming, including thermo-optic, free carrier dispersion, and Pockels effect result in either large device footprints or high static energy consumptions, significantly limiting their scalability. While chalcogenide-based non-volatile phase-change materials (PCMs) could mitigate these problems thanks to their strong index modulation and zero static power consumption, they often suffer from large absorptive loss, low cyclability, and lack of multilevel operation.

Ultra-low-energy programmable non-volatile silicon photonics based on phase-change materials with graphene heaters.

Silicon photonics is evolving from laboratory research to real-world applications with the potential to transform many technologies, including optical neural networks and quantum information processing. A key element for these applications is a reconfigurable switch operating at ultra-low programming energy-a challenging proposition for traditional thermo-optic or free carrier switches. Recent advances in non-volatile programmable silicon photonics based on phase-change materials (PCMs) provide an attractive solution to energy-efficient photonic switches with zero static power, but the programming energy density remains high (hundreds of attojoules per cubic nanometre).

Waveguide-Integrated van der Waals Heterostructure Mid-Infrared Photodetector with High Performance.

Extending the operation wavelength of silicon photonics to the mid-infrared (mid-IR) band will significantly benefit critical application areas, including health care, astronomy, and chemical sensing. However, a major hurdle for mid-IR silicon photonics has been the lack of high-speed, high-responsivity, and low noise-equivalent power (NEP) photodetectors. Here, we demonstrate a van der Waals (vdW) heterostructure mid-IR photodetector integrated on a silicon-on-insulator (SOI) waveguide.

Helicity-dependent continuous varifocal metalens based on bilayer dielectric metasurfaces.

Metasurfaces offer a unique platform to realize flat lenses, reducing the size and complexity of imaging systems and thus enabling new imaging modalities. In this paper, we designed a bilayer helicity-dependent continuous varifocal dielectric metalens in the near-infrared range. The first layer consists of silicon nanopillars and functions as a half-wave plate, providing the helicity-dependent metasurface by combining propagation phase and geometric phase.

Black Phosphorus Mid-Infrared Light-Emitting Diodes Integrated with Silicon Photonic Waveguides.

Light-emitting diodes (LEDs) based on III-V/II-VI materials have delivered a compelling performance in the mid-infrared (mid-IR) region, which enabled wide-ranging applications in sensing, including environmental monitoring, defense, and medical diagnostics. Continued efforts are underway to realize on-chip sensors via heterogeneous integration of mid-IR emitters on a silicon photonic chip, but the uptake of such an approach is limited by the high costs and interfacial strains, associated with the processes of heterogeneous integrations. Here, the black phosphorus (BP)-based van der Waals (vdW) heterostructures are exploited as room-temperature LEDs.

Nonvolatile Electrically Reconfigurable Integrated Photonic Switch Enabled by a Silicon PIN Diode Heater.

Reconfigurability of photonic integrated circuits (PICs) has become increasingly important due to the growing demands for electronic-photonic systems on a chip driven by emerging applications, including neuromorphic computing, quantum information, and microwave photonics. Success in these fields usually requires highly scalable photonic switching units as essential building blocks. Current photonic switches, however, mainly rely on materials with weak, volatile thermo-optic or electro-optic modulation effects, resulting in large footprints and high energy consumption.

Ultra-low mode volume on-substrate silicon nanobeam cavity.

We design and fabricate an on-substrate bowtie photonic crystal (PhC) cavity in silicon. By optimizing the bowtie shapes in the unit cells of the PhC cavity, the maximum of the electric field can be highly confined in the bowtie tips. Due to such confinement, an ultra-low mode volume of ∼0.

Broadband transparent optical phase change materials for high-performance nonvolatile photonics.

Optical phase change materials (O-PCMs), a unique group of materials featuring exceptional optical property contrast upon a solid-state phase transition, have found widespread adoption in photonic applications such as switches, routers and reconfigurable meta-optics. Current O-PCMs, such as Ge-Sb-Te (GST), exhibit large contrast of both refractive index (Δn) and optical loss (Δk), simultaneously. The coupling of both optical properties fundamentally limits the performance of many applications.

Author Correction: Ultra-thin high-efficiency mid-infraredtransmissive Huygens meta-optics.

The original version of this Article omitted the following from the Acknowledgements:'J.D. and H.

Ultra-thin high-efficiency mid-infrared transmissive Huygens meta-optics.

The mid-infrared (mid-IR) is a strategically important band for numerous applications ranging from night vision to biochemical sensing. Here we theoretically analyzed and experimentally realized a Huygens metasurface platform capable of fulfilling a diverse cross-section of optical functions in the mid-IR. The meta-optical elements were constructed using high-index chalcogenide films deposited on fluoride substrates: the choices of wide-band transparent materials allow the design to be scaled across a broad infrared spectrum.