Photocathode Physics for Photoinjectors 2018

Session

Session 10

Session 10

17 Oct 2018, 10:15

Pueblo Conference Room A (Hilton-Buffalo Thunder)

Conveners

Session 10: Theory and Computation - continued

• Dimitre Dimitrov (Tech-X Corp.)

81. Ab initio many-body calculations of the mean transverse energy for proposed high-brightness photocathode materials

Kevin Nangoi (Cornell University)

17/10/2018, 10:15

Session 10: Theory and Computation - continued

The state of the art in creating next-generation high-brightness electron beams requires that electrons emerge with mean transverse energy (MTE) of ~10 meV or lower. Identification of new, promising materials requires predictive understanding of the physics underlying photoemission. This talk will present our first-principles ab initio solid-state calculations of MTE for a variety of proposed...

63. Simulating Quantum Efficiency of Polarized Photocathodes

Dr Andrei Afanasev, Dr Eric Montgomery (Euclid Techlabs )

17/10/2018, 10:35

Session 9: Theory and Computation

Abstract

Obtaining high efficiency of polarized electron sources is a priority task, especially for the upcoming Electron-Ion Collider to be able to reach the luminosity needed to reach its physics goals [1].
In this presentation, we review several proposed methods and related simulations aimed at enhancing quantum efficiency (QE) of polarized GaAs photocathodes. Among recent significant...

64. Recent development on the modeling of laser induced electron emission

Dr Peng Zhang (Michigan State University)

17/10/2018, 10:55

Session 10: Theory and Computation - continued

Laser induced electron emission is important to the development of novel plasma and vacuum devices [1, 2],
compact electromagnetic radiation sources and accelerators, and time-resolved electron microscope. The rapid
development in nanotechnology and ultrafast laser optics has brought great opportunities to control electron
emission at ultrashort spatiotemporal scales and offers unprecedented...

65. Modeling quantum yield, emittance and surface roughness effects from metallic photocathodes

Dr Dimitre Dimitrov (Tech-X Corp.)

17/10/2018, 11:15

Session 10: Theory and Computation - continued

The thermal limit of the intrinsic emittance of photocathodes represents an important property
to measure experimentally and to understand theoretically. Detailed measurements of intrinsic
emittance have become possible in momentatron experiments. Moreover, recent developments
in material design have allowed growing photoemissive layers with controlled surface roughness.
Although analytical...

67. The Modeling of Delayed Photo-Emission Processes in PIC Codes

Dr John Petillo

17/10/2018, 11:35

Session 10: Theory and Computation - continued

The high quantum efficiency of modern cesiated Semiconductor photocathodes is a consequence of the
deeper penetration depth of the drive laser, a smaller (or absent) surface barrier, and - critically - the
tendency of the dominant scattering mechanism during electron transport to the surface to be less
effective at draining the initial energy of the photoexcited electron. As a consequence, a...

68. Predictive QE Models for PIC Codes Using DFT, TMA, Delay Models, and Optical Models

Dr Kevin Jensen (Naval Research Laboratory)

17/10/2018, 11:55

Session 10: Theory and Computation - continued

High brightness photo-generated electron bunches for next generation and x-ray FEL's and light sources rely on particle-in-cell codes used for their modeling and design. The codes in turn require predictive and accurate models of photocathode yield, emittance, emission promptness and beam characteristics based on accurate material and environmental parameters, but in a but in a manner that...