Riccardo Sapienza

Plasmonic quantum size effects in silver nanoparticles are dominated by interfaces and local environments

Plasmonic quantum size effects in silver nanoparticles are dominated by interfaces and local environments, Published online: 19 November 2018; doi:10.1038/s41567-018-0345-z

The origin of size-dependent shifts of surface plasmon resonances in metal nanoparticles has been controversial for decades. A combined experimental and theoretical study on silver samples and their environments now provides a quantitative picture.

Author(s): Kenta Takata and Masaya Notomi

By simply tuning gain and loss, it’s possible to create and control band gap and edge states in a gapless and topologically trivial one-dimensional resonator array.

[Phys. Rev. Lett. 121, 213902] Published Tue Nov 20, 2018

Nicolò Accanto, Clément Molinier, Dimitrii Tanese, Emiliano Ronzitti, Zachary L. Newman, Claire Wyart, Ehud Isacoff, Eirini Papagiakoumou, Valentina Emiliani
Optical wavefront shaping is a powerful technique to control the distribution of light in the focus of a microscope. This ability, combined with optogenetics, holds great promise for precise manipulation of neuronal activity with light. However, a deeper understanding of complex brain circuits ... [Optica 5, 1478-1491 (2018)]

Quantum fractals

Quantum fractals, Published online: 12 November 2018; doi:10.1038/s41567-018-0327-1

Electrons with fractional dimension have been observed in an artificial Sierpiński triangle, demonstrating their quantum fractal nature.

Author(s): Kirill Koshelev, Sergey Lepeshov, Mingkai Liu, Andrey Bogdanov, and Yuri Kivshar

We reveal that metasurfaces created by seemingly different lattices of (dielectric or metallic) meta-atoms with broken in-plane symmetry can support sharp high-Q resonances arising from a distortion of symmetry-protected bound states in the continuum. We develop a rigorous theory of such asymmetric ...

[Phys. Rev. Lett. 121, 193903] Published Fri Nov 09, 2018

Author(s): Ankan Bag, Martin Neugebauer, Paweł Woźniak, Gerd Leuchs, and Peter Banzer

Laser tricks allow nanoparticle position measurements with just 0.6-angstrom uncertainty, which will be useful in future nanotech devices.

[Phys. Rev. Lett. 121, 193902] Published Fri Nov 09, 2018

Author(s): Lei Wei, Anatoly V. Zayats, and Francisco J. Rodríguez-Fortuño

We propose a method for ultrasensitive displacement and phase measurements based on a nanoantenna illuminated with interfering evanescent waves. We show that with a proper nanoantenna design, tiny displacements and relative phase variations can be converted into changes of the scattering direction i...

[Phys. Rev. Lett. 121, 193901] Published Tue Nov 06, 2018

Plasmonic dynamics measured with frequency-comb-referenced phase spectroscopy

Plasmonic dynamics measured with frequency-comb-referenced phase spectroscopy, Published online: 05 November 2018; doi:10.1038/s41567-018-0330-6

By means of a novel referencing technique that is based on the high stability of frequency combs, broadband phase spectra from plasmonics rulers can now be used to measure dynamic motion of nanostructures with picometre resolution.

Wei Zhang, Aaron Charous, Masaya Nagai, Daniel M. Mittleman, Rajind Mendis
Accurately characterizing the width of a narrow (high Q) resonance can be quite challenging, requiring either a high-resolution grating spectrometer or a Fourier transform spectrometer with a long delay range. Here, we describe a new technique to determine the Q of a resonance based on spatial ... [Optica 5, 1414-1417 (2018)]

Microwave plasmonic mixer in a transparent fibre–wireless link

Microwave plasmonic mixer in a transparent fibre–wireless link, Published online: 29 October 2018; doi:10.1038/s41566-018-0281-6

A direct wireless-to-optical receiver in a transparent optical link is achieved, thanks to a subwavelength two-dimensionally localized gap-plasmon mixer encoding wireless information directly onto optical signals.

Luqi Yuan, Qian Lin, Meng Xiao, Shanhui Fan
The physics of a photonic structure is commonly described in terms of its apparent geometric dimensionality. On the other hand, with the concept of synthetic dimension, it is in fact possible to explore physics in a space with a dimensionality that is higher as compared to the apparent geometrical ... [Optica 5, 1396-1405 (2018)]

On the complexity and verification of quantum random circuit sampling

On the complexity and verification of quantum random circuit sampling, Published online: 29 October 2018; doi:10.1038/s41567-018-0318-2

Evidence is provided that quantum random circuit sampling, a near-term quantum computational task, is classically hard but verifiable, making it a leading proposal for achieving quantum supremacy.

Author(s): Alexander Büse, Mathieu L. Juan, Nora Tischler, Vincenzo D’Ambrosio, Fabio Sciarrino, Lorenzo Marrucci, and Gabriel Molina-Terriza

The fragile quantum state of a pair of entangled photons is undisturbed when the photons pass through a nanoscale hole, which may be useful in future light-based computing.

[Phys. Rev. Lett. 121, 173901] Published Fri Oct 26, 2018

Author(s): D. A. Dobrykh, A. V. Yulin, A. P. Slobozhanyuk, A. N. Poddubny, and Yu. S. Kivshar

Topological photonics has emerged recently as a smart approach for realizing robust optical circuitry, and the study of nonlinear effects is expected to open the door for tunability of photonic topological states. Here we realize experimentally nonlinearity-induced spectral tuning of electromagnetic...

[Phys. Rev. Lett. 121, 163901] Published Thu Oct 18, 2018

Yunzhe Li, Yujia Xue, Lei Tian
Imaging through scattering is an important yet challenging problem. Tremendous progress has been made by exploiting the deterministic input–output “transmission matrix” for a fixed medium. However, this “one-to-one” mapping is highly susceptible to speckle ... [Optica 5, 1181-1190 (2018)]