Letters

  • Letter |

    Inhomogeneity of the photogenerated carrier spacetime distribution enables transient symmetry breaking in a metasurface. As a result, broadband transient dichroism is demonstrated.

    • Andrea Schirato
    • , Margherita Maiuri
    • , Andrea Toma
    • , Silvio Fugattini
    • , Remo Proietti Zaccaria
    • , Paolo Laporta
    • , Peter Nordlander
    • , Giulio Cerullo
    • , Alessandro Alabastri
    •  & Giuseppe Della Valle
  • Letter |

    An experimental study of the second-harmonic-generation process in a beta barium borate crystal shows that homogeneous optical crystals can exhibit the rich physics of the spin–orbit angular momentum cascade in the nonlinear optical regime.

    • Yutao Tang
    • , Kingfai Li
    • , Xuecai Zhang
    • , Junhong Deng
    • , Guixin Li
    •  & Etienne Brasselet
  • Letter |

    The Kramers–Kronig approach is applied to high-capacity, free-space terahertz communications, bringing a greatly simplified receiver design.

    • T. Harter
    • , C. Füllner
    • , J. N. Kemal
    • , S. Ummethala
    • , J. L. Steinmann
    • , M. Brosi
    • , J. L. Hesler
    • , E. Bründermann
    • , A.-S. Müller
    • , W. Freude
    • , S. Randel
    •  & C. Koos
  • Letter |

    Moiré lattices optically induced in photorefractive nonlinear media are used to explain the formation of optical solitons under different geometrical conditions controlled by the twisting angle between the constitutive sublattices.

    • Qidong Fu
    • , Peng Wang
    • , Changming Huang
    • , Yaroslav V. Kartashov
    • , Lluis Torner
    • , Vladimir V. Konotop
    •  & Fangwei Ye
  • Letter |

    The findings that the spatial distribution of an optical field with vortex phase profile can be imprinted coherently onto a propagating electron wave reveal new aspects of light–matter interactions and will help develop future single-photon electron spectroscopy.

    • Giovanni De Ninno
    • , Jonas Wätzel
    • , Primož Rebernik Ribič
    • , Enrico Allaria
    • , Marcello Coreno
    • , Miltcho B. Danailov
    • , Christian David
    • , Alexander Demidovich
    • , Michele Di Fraia
    • , Luca Giannessi
    • , Klavs Hansen
    • , Špela Krušič
    • , Michele Manfredda
    • , Michael Meyer
    • , Andrej Mihelič
    • , Najmeh Mirian
    • , Oksana Plekan
    • , Barbara Ressel
    • , Benedikt Rösner
    • , Alberto Simoncig
    • , Simone Spampinati
    • , Matija Stupar
    • , Matjaž Žitnik
    • , Marco Zangrando
    • , Carlo Callegari
    •  & Jamal Berakdar
  • Letter |

    Gold atoms were stripped of up to 72 electrons by irradiating gold foils and nanowire arrays with a relativistic 400 nm laser pulse. This work will open the door to the study of the atomic physics of highly charged atoms in very-high-density plasmas.

    • R. Hollinger
    • , S. Wang
    • , Y. Wang
    • , A. Moreau
    • , M. G. Capeluto
    • , H. Song
    • , A. Rockwood
    • , E. Bayarsaikhan
    • , V. Kaymak
    • , A. Pukhov
    • , V. N. Shlyaptsev
    •  & J. J. Rocca
  • Letter |

    Observations of decoherence from thermodynamic noise in microresonator soliton frequency combs and laser cooling that reduces soliton thermal decoherence to far below the ambient-temperature limit are described, linking nonlinear photonics and microscopic fluctuations.

    • Tara E. Drake
    • , Jordan R. Stone
    • , Travis C. Briles
    •  & Scott B. Papp
  • Letter |

    An appropriately designed pulsed beam crossing an interface is shown to enable phenomena including anomalous group-velocity increase in higher-index materials, and tunable group velocity by varying the angle of incidence.

    • Basanta Bhaduri
    • , Murat Yessenov
    •  & Ayman F. Abouraddy
  • Letter |

    Owing to the superlattice-induced bandgap and superlattice-enhanced density of states, small-twist-angled (<2°) bilayer graphene exhibits a strong gate-tunable photoresponse in the mid-infrared regime of 5 to 12 μm, reaching an extrinsic peak responsivity of 26 mA W−1 at 12 μm.

    • Bingchen Deng
    • , Chao Ma
    • , Qiyue Wang
    • , Shaofan Yuan
    • , Kenji Watanabe
    • , Takashi Taniguchi
    • , Fan Zhang
    •  & Fengnian Xia
  • Letter |

    Exploiting two-dimensional metamaterials, the direction of emission from InGaN/GaN quantum wells is engineered while simultaneously improving quantum efficiency.

    • Prasad P. Iyer
    • , Ryan A. DeCrescent
    • , Yahya Mohtashami
    • , Guillaume Lheureux
    • , Nikita A. Butakov
    • , Abdullah Alhassan
    • , Claude Weisbuch
    • , Shuji Nakamura
    • , Steven P. DenBaars
    •  & Jon. A. Schuller
  • Letter |

    A pair of transportable optical lattice clocks with 10−18 uncertainty is developed. The relativistic redshift predicted by the theory of general relativity has been tested at the 10–5 level by the two optical clocks with a height difference of 450 m on the ground.

    • Masao Takamoto
    • , Ichiro Ushijima
    • , Noriaki Ohmae
    • , Toshihiro Yahagi
    • , Kensuke Kokado
    • , Hisaaki Shinkai
    •  & Hidetoshi Katori
  • Letter |

    An optoelectronic device that measures and suppresses the phase noise of a source has been realized in an integrated silicon platform.

    • Mohamad Hossein Idjadi
    •  & Firooz Aflatouni
  • Letter |

    Optically induced magnetization is experimentally demonstrated using gold nanoparticles. The inverse-Faraday-effect-enabled magnetization may lead to new types of compact optical isolator.

    • Oscar Hsu-Cheng Cheng
    • , Dong Hee Son
    •  & Matthew Sheldon
  • Letter |

    Phase-matching quantum key distribution is implemented with a 502 km ultralow-loss optical fibre. The fluctuations of the laser initial phases and frequencies are suppressed by the laser injection technique and the phase post-compensation method.

    • Xiao-Tian Fang
    • , Pei Zeng
    • , Hui Liu
    • , Mi Zou
    • , Weijie Wu
    • , Yan-Lin Tang
    • , Ying-Jie Sheng
    • , Yao Xiang
    • , Weijun Zhang
    • , Hao Li
    • , Zhen Wang
    • , Lixing You
    • , Ming-Jun Li
    • , Hao Chen
    • , Yu-Ao Chen
    • , Qiang Zhang
    • , Cheng-Zhi Peng
    • , Xiongfeng Ma
    • , Teng-Yun Chen
    •  & Jian-Wei Pan
  • Letter |

    A luminescent photonic substrate with a controlled angular emission profile is introduced and its ability to generate high-contrast dark-field images of micrometre-sized living organisms is demonstrated using standard optical microscopy equipment.

    • Cécile A. C. Chazot
    • , Sara Nagelberg
    • , Christopher J. Rowlands
    • , Maik R. J. Scherer
    • , Igor Coropceanu
    • , Kurt Broderick
    • , Yunjo Kim
    • , Moungi G. Bawendi
    • , Peter T. C. So
    •  & Mathias Kolle
  • Letter |

    A heralded squeezing gate with near unit fidelity is demonstrated, even for modest ancillary squeezing. A heralding filter is implemented in the feed-forward operation. With 6 dB of ancillary squeezing, a fidelity of 0.985 is experimentally obtained.

    • Jie Zhao
    • , Kui Liu
    • , Hao Jeng
    • , Mile Gu
    • , Jayne Thompson
    • , Ping Koy Lam
    •  & Syed M. Assad
  • Letter |

    A Sagnac gyroscope based on Brillouin ring lasers on a silicon chip is presented. The stability and sensitivity of this on-chip planar gyroscope allow measurement of the Earth’s rotation, with an amplitude sensitivity as small as 5 deg h−1 for a sinusoidal rotation, an angle random walk of 0.068 deg h−1/2 and bias instability of 3.6 deg h−1.

    • Yu-Hung Lai
    • , Myoung-Gyun Suh
    • , Yu-Kun Lu
    • , Boqiang Shen
    • , Qi-Fan Yang
    • , Heming Wang
    • , Jiang Li
    • , Seung Hoon Lee
    • , Ki Youl Yang
    •  & Kerry Vahala
  • Letter |

    Using a femtosecond mode-locked laser and a frequency-locked electric signal, a displacement measurement method that offers a >MHz measurement speed, sub-nanometre precision and a measurement range of more than several millimetres is achieved, facilitating the study of broadband, transient and nonlinear mechanical dynamics in real time.

    • Yongjin Na
    • , Chan-Gi Jeon
    • , Changmin Ahn
    • , Minji Hyun
    • , Dohyeon Kwon
    • , Junho Shin
    •  & Jungwon Kim
  • Letter |

    Femtosecond laser pulses are sent to a graphene/SiC interface to investigate photoinduced charge transfer from graphene to SiC. A charge transfer time of 300 attoseconds is obtained via laser-pulse-duration-dependent saturation fluence determination.

    • Christian Heide
    • , Martin Hauck
    • , Takuya Higuchi
    • , Jürgen Ristein
    • , Lothar Ley
    • , Heiko B. Weber
    •  & Peter Hommelhoff
  • Letter |

    A highly transparent photodetector using graphene as the light-sensing layer, conducting channel layer, gate layer and interconnects enables new approaches for light field photodetection and imaging involving simultaneous detection across multiple focal planes.

    • Miao-Bin Lien
    • , Che-Hung Liu
    • , Il Yong Chun
    • , Saiprasad Ravishankar
    • , Hung Nien
    • , Minmin Zhou
    • , Jeffrey A. Fessler
    • , Zhaohui Zhong
    •  & Theodore B. Norris
  • Letter |

    Embedding perovskite quantum dots in perovskite leads to bright, efficient 980 nm LEDs with applications in imaging and sensing.

    • Liang Gao
    • , Li Na Quan
    • , F. Pelayo García de Arquer
    • , Yongbiao Zhao
    • , Rahim Munir
    • , Andrew Proppe
    • , Rafael Quintero-Bermudez
    • , Chengqin Zou
    • , Zhenyu Yang
    • , Makhsud I. Saidaminov
    • , Oleksandr Voznyy
    • , Sachin Kinge
    • , Zhenghong Lu
    • , Shana O. Kelley
    • , Aram Amassian
    • , Jiang Tang
    •  & Edward H. Sargent
  • Letter |

    Programmable linear optical networks are implemented in a multimode fibre. The intermodal coupling between the spatial and polarization modes of the fibre is controlled by wavefront shaping. The network is used to emulate tunable coherent absorption.

    • Saroch Leedumrongwatthanakun
    • , Luca Innocenti
    • , Hugo Defienne
    • , Thomas Juffmann
    • , Alessandro Ferraro
    • , Mauro Paternostro
    •  & Sylvain Gigan
  • Letter |

    By designing wavefronts in the far field that have optimal properties in the near field, a general framework for optimal micromanipulation with targets of arbitrary shape and in arbitrarily complex environments, such as disordered media, is reported.

    • Michael Horodynski
    • , Matthias Kühmayer
    • , Andre Brandstötter
    • , Kevin Pichler
    • , Yan V. Fyodorov
    • , Ulrich Kuhl
    •  & Stefan Rotter
  • Letter |

    Luminescent CsPbBr3 quantum dots can be written into glass using femtosecond laser pulses and thermal annealing, and erased by further femtosecond laser irradiation. The resulting quantum dot patterns could prove useful for data storage, decoration or security purposes.

    • Xiongjian Huang
    • , Qianyi Guo
    • , Dandan Yang
    • , Xiudi Xiao
    • , Xiaofeng Liu
    • , Zhiguo Xia
    • , Fengjia Fan
    • , Jianrong Qiu
    •  & Guoping Dong
  • Letter |

    Careful harvesting of triplet excitons allows the realization of efficient green-emitting quasi-2D perovskite LEDs.

    • Chuanjiang Qin
    • , Toshinori Matsushima
    • , William J. Potscavage Jr
    • , Atula S. D. Sandanayaka
    • , Matthew R. Leyden
    • , Fatima Bencheikh
    • , Kenichi Goushi
    • , Fabrice Mathevet
    • , Benoît Heinrich
    • , Go Yumoto
    • , Yoshihiko Kanemitsu
    •  & Chihaya Adachi
  • Letter |

    Freely propagating, locally and globally chiral electric fields are introduced, enabling full control over intensity, polarization and propagation direction of the nonlinear enantio-sensitive optical response of randomly oriented chiral molecules.

    • David Ayuso
    • , Ofer Neufeld
    • , Andres F. Ordonez
    • , Piero Decleva
    • , Gavriel Lerner
    • , Oren Cohen
    • , Misha Ivanov
    •  & Olga Smirnova
  • Letter |

    An amplitude squeezed light source that operates down to 1 kHz frequencies—the lowest squeezing frequency—is generated in nonlinear crystal-based systems. By injecting the squeezed light into a microresonator, the quantum radiation pressure noise is reduced by 1.2 dB.

    • Min Jet Yap
    • , Jonathan Cripe
    • , Georgia L. Mansell
    • , Terry G. McRae
    • , Robert L. Ward
    • , Bram J. J. Slagmolen
    • , Paula Heu
    • , David Follman
    • , Garrett D. Cole
    • , Thomas Corbitt
    •  & David E. McClelland
  • Letter |

    Unusual photoemission from graphene is explained by the emission of hot electrons. The findings may lead to integrated photonic devices driven by hot-electron emission.

    • Fatemeh Rezaeifar
    • , Ragib Ahsan
    • , Qingfeng Lin
    • , Hyun Uk Chae
    •  & Rehan Kapadia
  • Letter |

    Responses to high-intensity mid-infrared laser light are theoretically investigated in the Haldane system. It is found that the primary electronic response, optical tunnelling and high-harmonic emission are sensitive to the topological phase of matter.

    • R. E. F. Silva
    • , Á. Jiménez-Galán
    • , B. Amorim
    • , O. Smirnova
    •  & M. Ivanov
  • Letter |

    Higher-order topologically protected states, localized to corners of photonic waveguide arrays, are experimentally demonstrated.

    • Ashraf El Hassan
    • , Flore K. Kunst
    • , Alexander Moritz
    • , Guillermo Andler
    • , Emil J. Bergholtz
    •  & Mohamed Bourennane
  • Letter |

    Using graphene as the ‘metal’ layer can increase the localization accuracy of metal-induced energy transfer, enabling axial localization of single emitters and measurement of the thickness of lipid bilayers with ångström accuracy.

    • Arindam Ghosh
    • , Akshita Sharma
    • , Alexey I. Chizhik
    • , Sebastian Isbaner
    • , Daja Ruhlandt
    • , Roman Tsukanov
    • , Ingo Gregor
    • , Narain Karedla
    •  & Jörg Enderlein
  • Letter |

    A violation of bilocal inequality is demonstrated with two truly independent light sources delivering entanglements to three nodes. To this end, the locality, measurement independence and quantum source independence loopholes are closed simultaneously.

    • Qi-Chao Sun
    • , Yang-Fan Jiang
    • , Bing Bai
    • , Weijun Zhang
    • , Hao Li
    • , Xiao Jiang
    • , Jun Zhang
    • , Lixing You
    • , Xianfeng Chen
    • , Zhen Wang
    • , Qiang Zhang
    • , Jingyun Fan
    •  & Jian-Wei Pan
  • Letter |

    Blue light-emitting diodes based on perovskite nanostructures embedded within quasi-two-dimensional phases show highly effective charge injection and suppressed non-radiative recombination.

    • Yang Liu
    • , Jieyuan Cui
    • , Kai Du
    • , He Tian
    • , Zhuofei He
    • , Qiaohui Zhou
    • , Zhaoliang Yang
    • , Yunzhou Deng
    • , Dong Chen
    • , Xiaobing Zuo
    • , Yang Ren
    • , Liang Wang
    • , Haiming Zhu
    • , Baodan Zhao
    • , Dawei Di
    • , Jianpu Wang
    • , Richard H. Friend
    •  & Yizheng Jin
  • Letter |

    A hybrid material based on uniform graphene on both the outer surface and inner hole walls of a photonic crystal fibre offers a strong, tunable light–matter interaction and good broadband electro-optic modulation performance under low gate voltage.

    • Ke Chen
    • , Xu Zhou
    • , Xu Cheng
    • , Ruixi Qiao
    • , Yi Cheng
    • , Can Liu
    • , Yadian Xie
    • , Wentao Yu
    • , Fengrui Yao
    • , Zhipei Sun
    • , Feng Wang
    • , Kaihui Liu
    •  & Zhongfan Liu
  • Letter |

    A sender and a receiver for continuous-variable quantum key distribution are packed onto separate silicon photonic chips. By using an external 1,550-nm laser, a secret key rate of 0.14 kbps is transmitted over a simulated distance of 100 km in fibre.

    • G. Zhang
    • , J. Y. Haw
    • , H. Cai
    • , F. Xu
    • , S. M. Assad
    • , J. F. Fitzsimons
    • , X. Zhou
    • , Y. Zhang
    • , S. Yu
    • , J. Wu
    • , W. Ser
    • , L. C. Kwek
    •  & A. Q. Liu
  • Letter |

    A high-speed wireless THz communication link is seamlessly integrated into a fibre-optic network. The demonstration relies on an ultra-broadband modulator exploiting two-dimensionally localized gap plasmons for direct conversion of the THz signals to the optical domain.

    • S. Ummethala
    • , T. Harter
    • , K. Koehnle
    • , Z. Li
    • , S. Muehlbrandt
    • , Y. Kutuvantavida
    • , J. Kemal
    • , P. Marin-Palomo
    • , J. Schaefer
    • , A. Tessmann
    • , S. K. Garlapati
    • , A. Bacher
    • , L. Hahn
    • , M. Walther
    • , T. Zwick
    • , S. Randel
    • , W. Freude
    •  & C. Koos
  • Letter |

    By using a single-quantum-well active region with a unique well–cladding design to suppress non-radiative recombination and enhance radiative recombination, light-emitting diodes with close to unity internal quantum efficiency at a low current density of <10−4 A cm−2 are demonstrated.

    • Ning Li
    • , Kevin Han
    • , William Spratt
    • , Stephen Bedell
    • , John Ott
    • , Marinus Hopstaken
    • , Frank Libsch
    • , Qinglong Li
    •  & Devendra Sadana