NAPAC2019 - List of Authors (Karkare, S.S.)

Paper	Title	Page
MOPLM15	Design of the ASU Photocathode Lab	132
SUPLH06	use link to see paper's listing under its alternate paper code
	C.J. Knill, S.S. Karkare Arizona State University, Tempe, USA J.V. Conway, B.M. Dunham, K.W. Smolenski Xelera Research LLC, Ithaca, New York, USA H.A. Padmore LBNL, Berkeley, California, USA
	Funding: This work was supported by the U.S. National Science Foundation under Award PHY-1549132, the Center for Bright Beams. Recent investigations have shown that it is possible to obtain an order of magnitude smaller intrinsic emittance from photocathodes by precise atomic scale control of the surface, using an appropriate electronic band structure of single crystal cathodes and cryogenically cooling the cathode. Investigating the performance of such cathodes requires atomic scale surface diagnostic techniques connected in ultra-high vacuum (UHV) to the epitaxial thin film growth and surface preparation systems and photo-emission and photocathode diagnostic techniques. Here we report the capabilities and design of the laboratory being built at the Arizona State University for this purpose. The lab houses a 200 kV DC gun with a cryogenically cooled cathode along with a beam diagnostics and ultra fast electron diffraction beamline. The cathode of the gun can be transported in UHV to a suite of UHV growth chambers and surface and photoemission diagnostic techniques.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOPLM15
About •	paper received ※ 26 August 2019 paper accepted ※ 04 September 2019 issue date ※ 08 October 2019
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MOPLM16	Design of a 200 kV DC Cryocooled Photoemission Gun for Photocathode Investigations	136
SUPLH01	use link to see paper's listing under its alternate paper code
	G.S. Gevorkyan, S.S. Karkare Arizona State University, Tempe, USA I.V. Bazarov, A. Galdi, J.M. Maxson Cornell University, Ithaca, New York, USA L. Cultrera, W.H. Li Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: This work was supported by the U.S. National Science Foundation under Award No. PHY-1549132, the Center for Bright Beams. Intrinsic emittance of photocathodes limits the brightness of electrons beams produced from photoemission guns. Recent advancements have shown that an order of magnitude improvement in intrinsic emittance over the commonly used polycrystalline metal and semiconductor cathodes is possible via use of single crystalline ordered surfaces of metals, semiconductors and other exotic materials at cryogenic temperatures as cathodes. However, due to practical design considerations, it is not trivial to test such cathodes in existing electron guns. Here we present the design of a 200kV DC electron gun being developed at the Arizona State University for this purpose.
	Poster MOPLM16 [1.549 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOPLM16
About •	paper received ※ 27 August 2019 paper accepted ※ 12 September 2019 issue date ※ 08 October 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPLH09	Photoluminescence Studies of Alkali-Antimonide Photocathodes	188
SUPLE01	use link to see paper's listing under its alternate paper code
	P. Saha, O. Chubenko, S.S. Karkare Arizona State University, Tempe, USA H.A. Padmore LBNL, Berkeley, California, USA
	Alkali-antimonide photocathodes have a very high quantum efficiency and a low intrinsic emittance, making them excellent electron sources for Energy Recovery Linacs, X-ray Free Electron Lasers, Electron Cooling, and Ultrafast Electron Diffraction applications. Despite numerous studies of their photoemission spectra, there has been nearly no conclusive experimental investigation of their basic electronic and optical properties (e.g. band gap, electron affinity, optical constants, etc.), which determine the nature of photoemission. Therefore, the systematic study and deep understanding of fundamental characteristics of alkali-antimonide photocathodes are required in order to develop next-generation electron sources with improved crystal and electronic structures to fit specific application. Here we report on the development of an experimental setup to measure photoluminescence (PL) spectra from alkali-antimonide photocathodes, enabling estimation of a material band gap and defect state energies, and provide preliminary results for Cs3Sb films.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOPLH09
About •	paper received ※ 27 August 2019 paper accepted ※ 04 September 2019 issue date ※ 08 October 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

MOPLM15

Design of the ASU Photocathode Lab

132

SUPLH06

use link to see paper's listing under its alternate paper code

C.J. Knill, S.S. Karkare
Arizona State University, Tempe, USA
J.V. Conway, B.M. Dunham, K.W. Smolenski
Xelera Research LLC, Ithaca, New York, USA
H.A. Padmore
LBNL, Berkeley, California, USA

Funding: This work was supported by the U.S. National Science Foundation under Award PHY-1549132, the Center for Bright Beams.
Recent investigations have shown that it is possible to obtain an order of magnitude smaller intrinsic emittance from photocathodes by precise atomic scale control of the surface, using an appropriate electronic band structure of single crystal cathodes and cryogenically cooling the cathode. Investigating the performance of such cathodes requires atomic scale surface diagnostic techniques connected in ultra-high vacuum (UHV) to the epitaxial thin film growth and surface preparation systems and photo-emission and photocathode diagnostic techniques. Here we report the capabilities and design of the laboratory being built at the Arizona State University for this purpose. The lab houses a 200 kV DC gun with a cryogenically cooled cathode along with a beam diagnostics and ultra fast electron diffraction beamline. The cathode of the gun can be transported in UHV to a suite of UHV growth chambers and surface and photoemission diagnostic techniques.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOPLM15

About •

paper received ※ 26 August 2019 paper accepted ※ 04 September 2019 issue date ※ 08 October 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPLM16

Design of a 200 kV DC Cryocooled Photoemission Gun for Photocathode Investigations

136

SUPLH01

use link to see paper's listing under its alternate paper code

G.S. Gevorkyan, S.S. Karkare
Arizona State University, Tempe, USA
I.V. Bazarov, A. Galdi, J.M. Maxson
Cornell University, Ithaca, New York, USA
L. Cultrera, W.H. Li
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: This work was supported by the U.S. National Science Foundation under Award No. PHY-1549132, the Center for Bright Beams.
Intrinsic emittance of photocathodes limits the brightness of electrons beams produced from photoemission guns. Recent advancements have shown that an order of magnitude improvement in intrinsic emittance over the commonly used polycrystalline metal and semiconductor cathodes is possible via use of single crystalline ordered surfaces of metals, semiconductors and other exotic materials at cryogenic temperatures as cathodes. However, due to practical design considerations, it is not trivial to test such cathodes in existing electron guns. Here we present the design of a 200kV DC electron gun being developed at the Arizona State University for this purpose.

Poster MOPLM16 [1.549 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOPLM16

About •

paper received ※ 27 August 2019 paper accepted ※ 12 September 2019 issue date ※ 08 October 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPLH09

Photoluminescence Studies of Alkali-Antimonide Photocathodes

188

SUPLE01

use link to see paper's listing under its alternate paper code

P. Saha, O. Chubenko, S.S. Karkare
Arizona State University, Tempe, USA
H.A. Padmore
LBNL, Berkeley, California, USA

Alkali-antimonide photocathodes have a very high quantum efficiency and a low intrinsic emittance, making them excellent electron sources for Energy Recovery Linacs, X-ray Free Electron Lasers, Electron Cooling, and Ultrafast Electron Diffraction applications. Despite numerous studies of their photoemission spectra, there has been nearly no conclusive experimental investigation of their basic electronic and optical properties (e.g. band gap, electron affinity, optical constants, etc.), which determine the nature of photoemission. Therefore, the systematic study and deep understanding of fundamental characteristics of alkali-antimonide photocathodes are required in order to develop next-generation electron sources with improved crystal and electronic structures to fit specific application. Here we report on the development of an experimental setup to measure photoluminescence (PL) spectra from alkali-antimonide photocathodes, enabling estimation of a material band gap and defect state energies, and provide preliminary results for Cs3Sb films.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2019-MOPLH09

About •

paper received ※ 27 August 2019 paper accepted ※ 04 September 2019 issue date ※ 08 October 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)