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  • Highly efficient perovskite solar cells have been fabricated by using room-temperature deposition processes. The cells are based on a layer of methylammonium lead iodide perovskite that is prepared by sublimation in a high-vacuum chamber and sandwiched between two thin organic charge-transport layers.

    • Olga Malinkiewicz
    • Aswani Yella
    • Henk J. Bolink
    Letter
  • Temporal dissipative solitons are observed in a nonlinear, high-finesse, optical microresonator driven by a continuous-wave laser. This approach enables ultrashort pulses to be generated in spectral regimes lacking broadband laser gain media and saturable absorbers, making it potentially useful for applications in broadband spectroscopy, telecommunications, astronomy and low-phase-noise microwave generation.

    • T. Herr
    • V. Brasch
    • T. J. Kippenberg
    Article
  • Single-step fabrication of a multimode quantum resource from the parametric downconversion of femtosecond frequency combs is demonstrated. Each of the 511 possible bipartitions among ten spectral regions is shown to be entangled. Furthermore, an eigenmode decomposition reveals that eight independent quantum channels (qumodes) are subsumed within the comb.

    • Jonathan Roslund
    • Renné Medeiros de Araújo
    • Nicolas Treps
    Letter
  • Simultaneous detection of electric and magnetic fields with a subwavelength resolution is achieved by a near-field scanning approach. Additionally, theoretical considerations provide guidelines for designing probes sensitive to specific desired combinations of electric- and magnetic-field components.

    • B. le Feber
    • N. Rotenberg
    • L. Kuipers
    Letter
  • A silicon-on-insulator device combining two four-wave-mixing photon-pair sources in an interferometer with a reconfigurable phase shifter is used to create and manipulate non-degenerate or degenerate, path-entangled or path-unentangled photon pairs. A quantum interference visibility of nearly 100% is observed on-chip. This device is a first step towards fully integrated quantum technologies.

    • J. W. Silverstone
    • D. Bonneau
    • M. G. Thompson
    Letter
  • An optical-field-driven streak camera for the temporal characterization (with potentially attosecond resolution) of ultrashort free-electron pulses at 25 keV is demonstrated. It involves intersecting an electron beam and a laser beam at a thin metal mirror.

    • F. O. Kirchner
    • A. Gliserin
    • P. Baum
    Article
  • Little is known about triplet excitons in semiconducting single-walled nanotubes, despite their importance in various applications. The pump–probe and spin-sensitive photoluminescence of such nanotubes is studied, and the quantum yield of triplet formation, triplet lifetime and triplet exciton size are found to be 5 ± 2%, 30 ± 10 µs and 0.65 nm, respectively.

    • Dominik Stich
    • Florian Späth
    • Tobias Hertel
    Article
  • Clear evidence is presented for the origins of photocurrent generation in metallic and semiconducting carbon nanotubes — photocurrent is found to be mainly generated by photothermal and photovoltaic effects in metallic and semiconducting carbon nanotubes, respectively. This finding will enable the engineering of highly efficient carbon-based photodetectors and energy-harvesting devices.

    • Maria Barkelid
    • Val Zwiller
    Letter
  • Perpendicular photoswitching of the polarization plane of the output second-harmonic light is observed in a chiral spin-crossover assembly based on an iron-octacyanoniobate magnet. This photoswitching can be reversed by irradiating with blue or red light. It originates from alternate photoswitching between the crystallographic and magnetic contributions to second-harmonic generation.

    • Shin-ichi Ohkoshi
    • Shinjiro Takano
    • Hiroko Tokoro
    Article
  • Room-temperature lasing in core–shell–cap GaAs/AlGaAs/GaAs nanowires is demonstrated using optical pumping. It is realized by employing a Fabry–Pérot cavity along with material optimization and surface recombination minimization. This demonstration should prove useful for designing nanoscale optoelectronic devices operating at near-infrared wavelengths.

    • Dhruv Saxena
    • Sudha Mokkapati
    • Chennupati Jagadish
    Letter
  • A continuous-variable cluster state containing more than 10,000 entangled modes is deterministically generated and fully characterized. The developed time-domain multiplexing method allows each quantum mode to be manipulated by the same optical components at different times. An efficient scheme for measurement-based quantum computation on this cluster state is presented.

    • Shota Yokoyama
    • Ryuji Ukai
    • Akira Furusawa
    Letter
  • The carrier-envelope phase of laser fields at metal tips can affect the generation and motion of strong-field emitted electrons. Observed variations in the width of plateau-like photoelectron spectra characteristic of the sub-cycle regime may lead to the control of coherent electron motion at metallic nanostructures on ultrashort lengths and timescales.

    • Björn Piglosiewicz
    • Slawa Schmidt
    • Christoph Lienau
    Letter
  • An easily implementable reconstruction scheme is demonstrated for determining the full vectorial amplitude and relative phase distributions of highly confined electromagnetic fields with subwavelength resolution from a single-scan measurement. This scheme will help improve microscopy and nanoscopy techniques.

    • Thomas Bauer
    • Sergej Orlov
    • Gerd Leuchs
    Letter
  • A new laser-field measurement technique is demonstrated that exploits nonlinear optical mixing in a gas in which attosecond pulses are being generated. The instantaneous field of an unknown pulse is imprinted onto the deflection of an attosecond pulse using an all-optical set-up with a bandwidth of up to 1 PHz.

    • Kyung Taec Kim
    • Chunmei Zhang
    • P. B. Corkum
    Letter
  • Two-, three- and higher multiphoton absorption processes are shown to occur in amyloid protein fibres, which are thought to play a role in various diseases, including Alzheimer's and Parkinson's diseases. The nonlinear optical behaviour of such proteins may also be useful for fabricating photonics devices.

    • Piotr Hanczyc
    • Marek Samoc
    • Bengt Norden
    Letter