All-optical control and metrology of electron pulses

Abstract

Short electron pulses are central to time-resolved atomic-scale diffraction and electron microscopy, streak cameras, and free-electron lasers. We demonstrate phase-space control and characterization of 5-picometer electron pulses using few-cycle terahertz radiation, extending concepts of microwave electron pulse compression and streaking to terahertz frequencies. Optical-field control of electron pulses provides synchronism to laser pulses and offers a temporal resolution that is ultimately limited by the rise-time of the optical fields applied. We used few-cycle waveforms carried at 0.3 terahertz to compress electron pulses by a factor of 12 with a timing stability of <4 femtoseconds (root mean square) and measure them by means of field-induced beam deflection (streaking). Scaling the concept toward multiterahertz control fields holds promise for approaching the electronic time scale in time-resolved electron diffraction and microscopy.

Attosecond electron pulse trains and quantum state reconstruction in ultrafast transmission electron microscopy

“…Ultrafast imaging and spectroscopy with electrons and x-rays are the basis for an ongoing revolution in the understanding of dynamical processes in matter on atomic scales [10][11][12][13] . The underlying technology heavily rests on laser science for the 2 generation and characterization of ever-shorter femtosecond electron 10,14 and xray [15][16][17] probe pulses, with examples in optical pulse compression 18 and streaking spectroscopy [19][20][21] . The temporal structuring of electron probe beams is facilitated by time-dependent fields in the radio-frequency [22][23][24] , terahertz 18,25 or optical domains.…”

“…The underlying technology heavily rests on laser science for the 2 generation and characterization of ever-shorter femtosecond electron 10,14 and xray [15][16][17] probe pulses, with examples in optical pulse compression 18 and streaking spectroscopy [19][20][21] . The temporal structuring of electron probe beams is facilitated by time-dependent fields in the radio-frequency [22][23][24] , terahertz 18,25 or optical domains. Promising a further leap in temporal resolution, recent findings suggest that ultrafast electron diffraction and microscopy with optically phasecontrolled and sub-cycle, attosecond-structured wave functions may be feasible 8,[26][27][28][29][30] .…”

Time-resolved electron(e,2e)momentum spectroscopy: Application to laser-driven electron population transfer in atoms

“…Studies of time-resolved electron dynamics in various atomic, molecular, and condensed-matter reactions have increased over the past two decades [1][2][3][4][5][6][7] owing to experimental progress in generating ultrashort and/or intense pulses of extreme ultraviolet light [8,9], x rays [10,11], and electrons [12,13]. These advances open the possibility of obtaining a deeper understanding of physical and chemical reaction mechanisms.…”

Implementation and modeling of a femtosecond laser-activated streak camera

“…These time-varying streaking fields have been generated using a microwave cavity, 19 a laser standing wave, 21-23 a discharging capacitor, 4,24 a split ring resonator, 25 and a terahertz resonator. 27 A laser-activated streak camera is susceptible to time of arrival jitter between the laser and electron pulses. If the signal is averaged over many shots, the streak camera measures the convolution of the electron pulse duration with the time of arrival jitter.…”

“…Different methods have been proposed and developed to measure the duration of electron pulses using streaking fields. 4,[20][21][22][23][24][25][26][27] Earlier versions of streak cameras were developed to measure the duration of x-ray pulses. [28][29][30][31][32][33][34][35][36][37][38][39][40] This method worked by first converting the x-ray pulse to an electron pulse in a photoemission process.…”