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Field-emission patterns from a clean tungsten tip apex induced by femtosecond laser pulses have been investigated. Strongly asymmetric field-emission intensity distributions are observed depending on three parameters: (1) the polarization…

Irradiation of sharp silver tips with femtosecond laser pulses leads to photoassisted coherent field emission without a static field. We reconstruct the time profile of the emission, and show that the process is entirely governed by the…

We show that a field emission tip electron source that is triggered with a femtosecond laser pulse can generate electron pulses shorter than the laser pulse duration (~100 fs). The emission process is sensitive to a power law of the laser…

We present femtosecond laser-induced electron emission from nanodiamond-coated tungsten tips. Based on the shortness of the femtosecond laser pulses, electrons can be photo-excited for wavelengths from the infrared (1932 nm) to the…

Applied Physics · Physics 2019-10-09 Alexander Tafel , Stefan Meier , Juergen Ristein , Peter Hommelhoff

We present energy-resolved measurements of electron emission from sharp metal tips driven with low energy pulses from a few-cycle laser oscillator. We observe above-threshold photoemission with a photon order of up to 9. At a laser…

Quantum Physics · Physics 2010-12-30 Markus Schenk , Michael Krüger , Peter Hommelhoff

The emission times of laser-triggered electrons from a sharp tungsten tip are directly characterized under ultrafast, near-infrared laser excitation at Keldysh parameters $6.6< \gamma < 19.1$. Emission delays up to 10 fs are observed, which…

We present a theoretical investigation of the yet unexplored dynamics of the produced excited carriers upon irradiation of hexagonal Silicon Carbide (6H-SiC) with femtosecond laser pulses. To describe the ultrafast behaviour of laser…

Materials Science · Physics 2020-03-04 G. D. Tsibidis , L. Mouchliadis , M. Pedio , E. Stratakis

Photoelectron field emission, induced by femtosecond laser pulses focused on metallic nanotips, provides spatially coherent and temporally short electron pulses. The properties of the photoelectron yield give insight into both the material…

Applied Physics · Physics 2021-05-17 Eric R. Jones , Wayne Cheng-Wei Huang , Gobind Basnet , Bret N. Flanders , Herman Batelaan

We determine the laser-induced ablation threshold fluence in air of aluminum and tungsten excited by single near-infrared laser pulses with duration ranging from 15 fs to 100 fs. The ablation threshold fluence is shown constant for both…

Optics · Physics 2020-11-02 T. Genieys , M. Sentis , O. Utéza

We have investigated field emission patterns from a clean tungsten tip apex induced by femtosecond laser pulses. Strongly asymmetric modulations of the field emission intensity distributions are observed depending on the polarization of the…

We present an experimental and numerical study of electron emission from a sharp tungsten tip triggered by sub-8 femtosecond low power laser pulses. This process is non-linear in the laser electric field, and the non-linearity can be tuned…

Quantum Physics · Physics 2007-05-23 Peter Hommelhoff , Catherine Kealhofer , Mark A. Kasevich

Using high-resolution, two-dimensional particle-in-cell simulations, we investigate numerically the mechanisms of terahertz (THz) emissions in submicron-thick carbon solid foils driven by ultraintense ($\sim 10^{20}\,\rm W\,cm^{-2}$),…

Plasma Physics · Physics 2020-07-10 J. Déchard , X. Davoine , L. Gremillet , L. Bergé

Since graphene has no band gap, photoluminescence is not expected from relaxed charge carriers. We have, however, observed significant light emission from graphene under excitation by ultrashort (30-fs) laser pulses. Light emission was…

Mesoscale and Nanoscale Physics · Physics 2010-09-20 Chun Hung Lui , Kin Fai Mak , Jie Shan , Tony F. Heinz

We present an experiment studying the interaction of a strongly focused 25 fs laser pulse with a tungsten nanotip, investigating the different regimes of laser-induced electron emission. We study the dependence of the electron yield with…

The heating of the electronic distribution of a copper photocathode due to an intense drive laser pulse is calculated under the two-temperature model using fluences and pulse lengths typical in RF photoinjector operation. Using the finite…

Accelerator Physics · Physics 2018-03-14 J. Maxson , P. Musumeci , L. Cultrera , S. Karkare , H. Padmore

A semi-empirical model is presented for the thermalized temperature $T$ and mean momentum in the direction of laser propagation <$p_{fz}$> of electrons released from O$_{2}$ after the passage of a focused $800$ nm ultrashort pulsed laser…

Plasma Physics · Physics 2025-09-16 Edward L. Ruden

Ultrafast laser induced thermionic emission from metal surfaces has several applications. Here, we investigate the role of laser polarization and angle of incidence on the ultrafast thermionic emission process from laser driven gold coated…

Frequency up-conversion of a few low-energy photons into a single high-energy photon contributes to imaging, light sources, and detection. However, the up-converting of many photons exhibits negligible efficiency. Up-conversion through…

Optics · Physics 2018-09-03 Dafna Granot , Nimrod Kruger , Assaf Manor , Carmel Rotschild

Ultrafast laser excitation can induce fast increases of the electronic subsystem temperature. The subsequent electronic evolutions in terms of band structure and energy distribution can determine the change of several thermodynamic…

Materials Science · Physics 2015-03-25 Emile Bévillon , Jean-Philippe Colombier , Vanina Recoules , Razvan Stoian

We report on sub-cycle terahertz light-field emission of electrons from tungsten nanotips under extreme conditions corresponding to a Keldysh parameter $\gamma_K\approx10^{-4}$. Local peak THz fields up to 40~GV/m are achieved at the apex…

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