Publications associées à Hertz

500 GHz field-resolved detection in thin-film lithium niobate devices

Ileana-Cristina Benea-Chelmus, Alessandro Tomasino

In this work, we show the coherent reconstruction of terahertz (THz) transients in thin-film lithium niobate integrated photonics circuits. Our devices modulate the intensity of a probe beam guided through a Mach-Zehnder interferometer (MZI) structure, und ...

IEEE2023

Time-Domain Integration of Broadband Terahertz Pulses via Tapered Two-Wire Waveguide

Alessandro Tomasino

In this work, we report on the implementation of a time-domain integrator device operating on arbitrary broadband Terahertz (THz) pulses. This analog signal-processing functionality is implemented by employing a two-wire waveguide (TWWG) variant, based on ...

IEEE2023

Broadband spectroscopy and inelastic light scattering on the canted antiferromagnet hematite for antiferromagnetic magnonics

Mohammad Hamdi

Collective spin excitations propagating in magnetically ordered materials are called spin waves (SWs) or magnons. They are promising for low-power and beyond-CMOS information processing, which do not suffer from the ohmic losses. SWs in ferromagnets (antif ...

EPFL2023

Ultrafast Electron Microscopy of Nanoscale Charge Dynamics in Semiconductors

Fabrizio Carbone, Ivan Madan, Giovanni Maria Vanacore, Ido Kaminer, Simone Gargiulo, Francesco Barantani, Kangpeng Wang

The ultrafast dynamics of charge carriers in solids plays a pivotal role in emerging optoelectronics, photonics, energy harvesting, and quantum technology applications. However, the investigation and direct visualization of such nonequilibrium phenomena re ...

AMER CHEMICAL SOC2023

Ultra-broadband terahertz radiation by supercontinuum generation and optical rectification in a dispersion-engineered waveguide: a numerical study

Ileana-Cristina Benea-Chelmus, Aleksei Gaier

In this work, we propose a numerical approach based on forward coupled mode modeling to simultaneously evaluate second- and third-order nonlinearities inside a dispersion-engineered waveguide towards the goal of generating broadband terahertz (THz) radiati ...

IEEE2023

Electronic metadevices for terahertz applications

Elison de Nazareth Matioli, Mohammad Samizadeh Nikooytabalvandani

The evolution of electronics has largely relied on downscaling to meet the continuous needs for faster and highly integrated devices(1). As the channel length is reduced, however, classic electronic devices face fundamental issues that hinder exploiting ma ...

NATURE PORTFOLIO2023

Development of Thin Film Lithium Niobate Shear Bulk Acoustic Wave Resonators

Soumya Yandrapalli

RF MEMS piezoelectric acoustic resonators are the essential building blocks for RF filters used in RF front-end modules for wireless mobile communication due to their compact size in the MHz-GHz frequency range, high Quality factors and large relative band ...

EPFL2022

Subthreshold VO2 vertical switches for large-bandwidth millimeter-wave and sub-terahertz detection

Mihai Adrian Ionescu, Ali Gilani, Daesung Park, Fatemeh Qaderi Rahaqi

n-linear impedance characteristics of VO2 offer solutions to highly sensitive radio-frequency (RF), millimeterwave (mm-wave), and terahertz (THz) detectors. We demonstrate high-speed broadband sensibility of miniaturized VO2 switches by utilizing the nonli ...

IEEE2022

Gigahertz free-space electro-optic modulators based on Mie resonances

Ileana-Cristina Benea-Chelmus, Sydney Rebecca Mason

Electro-optic modulators are essential for sensing, metrology and telecommunications. Most target fiber applications. Instead, metasurface-based architectures that modulate free-space light at gigahertz (GHz) speeds can boost flat optics technology by micr ...

Nature Portfolio2022

Direct observation of multiband transport in magnonic Penrose quasicrystals via broadband and phase-resolved spectroscopy

Dirk Grundler, Sho Watanabe, Mohammad Hamdi, Vinayak Shantaram Bhat, Korbinian Baumgärtl

Quasicrystals are aperiodically ordered structures with unconventional rotational symmetry. Their peculiar features have been explored in photonics to engineer bandgaps for light waves. Magnons (spin waves) are collective spin excitations in magnetically o ...

2021

Coherent terahertz-to-microwave link using electro-optic-modulated Turing rolls

Tobias Kippenberg, Anat Siddharth, Wenle Weng, Arslan Sajid Raja, Jijun He, Miles Henry Anderson

Arising from modulation instability, Turing rolls in optical Kerr microresonators have been used in the generation of optical frequency combs and the synthesis of microwave and terahertz frequencies. In this work, by applying electro-optic modulation on te ...

AMER PHYSICAL SOC2021

Monolithic piezoelectric control of soliton microcombs

Tobias Kippenberg, Rui Ning Wang, Junqiu Liu, Erwan Guillaume Albert Lucas, Wenle Weng, Arslan Sajid Raja, Jijun He, Miles Henry Anderson, Tianyi Liu

High-speed actuation of laser frequency(1)is critical in applications using lasers and frequency combs(2,3), and is a prerequisite for phase locking, frequency stabilization and stability transfer among optical carriers. For example, high-bandwidth feedbac ...

NATURE PUBLISHING GROUP2020

Nonlinear THz spectroscopy and simulation of gated graphene

Juan Ramon Mosig, Matthias Gäumann, Michele Tamagnone

We studied the nonlinear optical properties of single layer graphene using high terahertz (THz) fields. With the use of a back gate and cooling down the sample to cryogenic temperatures we are able to spectrally probe the nonlinear THz properties of intrin ...

IOP PUBLISHING LTD2018

Low frequency terahertz-induced demagnetization in ferromagnetic nickel

Christoph Peter Hauri, Mostafa Shalaby

A laser stimulus at terahertz (THz) frequency is expected to offer superior control over magnetization dynamics compared to an optical pulse, where ultrafast demagnetization is mediated by heat deposition. As a THz field cycle occurs on a timescale similar ...

Amer Inst Physics2016

Temporal and spectral shaping of broadband terahertz pulses in a photoexcited semiconductor

Christoph Peter Hauri, Mostafa Shalaby

Transmission through a photoexcited semiconductor is used to temporally and spectrally shape a terahertz (THz) pulse. By adjusting the optical pump-THz probe delay, we experimentally introduce a polar asymmetry in the pulse profile as large as 92%. To shap ...

AIP American Institute of Physics2015

Intense, carrier frequency and bandwidth tunable quasi single-cycle pulses from an organic emitter covering the Terahertz frequency gap

Christoph Peter Hauri

In Terahertz (THz) science, one of the long-standing challenges has been the formation of spectrally dense, single-cycle pulses with tunable duration and spectrum across the frequency range of 0.1–15 THz (THz gap). This frequency band, lying between the el ...

Nature Publishing Group2015

Spectrally intense terahertz source based on triangular Selenium

Christoph Peter Hauri, Mostafa Shalaby

The intensity of a nonlinear terahertz (THz) source is primarily given by its spectral density. In this letter, we introduce triangular Selinium (Se) as a novel THz emitter and show numerically its superior properties to the currently used crystals for int ...

Nature Publishing Group2015

High-performing nonlinear visualization of terahertz radiation on a silicon charge-coupled device

Christoph Peter Hauri, Mostafa Shalaby

Photoinduced electron transitions can lead to significant changes of the macroscopic electronic properties in semiconductors. This principle is responsible for the detection of light with charge-coupled devices. Their spectral sensitivity is limited by the ...

Nature Publishing Group2015

A nanoscale gigahertz source realized with Josephson scanning tunneling microscopy

Klaus Kern, Markus Etzkorn, Matthias Alexander Eltschka, Maximilian Assig

Using the AC Josephson effect in the superconductor-vacuum-superconductor tunnel junction of a scanning tunneling microscope (STM), we demonstrate the generation of GHz radiation. With the macroscopic STM tip acting as a lambda/4-monopole antenna, we first ...

Amer Inst Physics2015

Gate-controlled mid-infrared light bending with aperiodic graphene nanoribbons array

Juan Ramon Mosig, Julien Perruisseau-Carrier, Michele Tamagnone

Graphene plasmonic nanostructures enable subwavelength confinement of electromagnetic energy from the mid-infrared down to the terahertz frequencies. By exploiting the spectrally varying light scattering phase at the vicinity of the resonant frequency of t ...

Institute of Physics2015