IPAC2014 - List of Authors (Antipov, S.P.)

Paper	Title	Page
TUPME058	The Argonne Wakefield Accelerator (AWA): Commissioning and Operation	1503
	M.E. Conde, S.P. Antipov, D.S. Doran, W. Gai, C.-J. Jing, C. Li, W. Liu, J.G. Power, J.Q. Qiu, J.H. Shao, C. Whiteford, E.E. Wisniewski ANL, Argonne, Illinois, USA S.P. Antipov, C.-J. Jing, J.Q. Qiu Euclid TechLabs, LLC, Solon, Ohio, USA S. Cao IMP, Lanzhou, People's Republic of China C. Li, J.H. Shao TUB, Beijing, People's Republic of China E.E. Wisniewski Illinois Institute of Technology, Chicago, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy under contract No. DE-AC02-06CH11357. The commissioning of the upgraded AWA facility is well underway. The new L-band electron gun has been fully commissioned and has been successfully operated with its Cesium Telluride photocathode at a gradient of 80 MV/m. Single bunches of up to 100 nC, and bunch trains of four bunches with up to 80 nC per bunch have been generated. The six new accelerating cavities (L-band, seven cells, pi mode) have been RF conditioned to 12 MW or more; their operation at 10 MW brings the beam energy up to 75 MeV. Measurements of the beam parameters are presently underway, and the use of this intense beam to drive high gradient wakefields will soon follow. One of the main goals of the facility is to generate RF pulses with GW power levels, corresponding to accelerating gradients of hundreds of MV/m and energy gains on the order of 100 MeV per structure.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME058
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MOPRI058	Metal Plasmonic Nanostructures Functionalized by Atomic Layer Deposition of MgO for Photocathode Applications	739
	S.V. Baryshev, S.P. Antipov, A. Kanareykin Euclid TechLabs, LLC, Solon, Ohio, USA M.R. Savina, A.V. Zinovev ANL, Argonne, Illinois, USA E. Thimsen University of Minnesota, Minneapolis, USA
	Funding: Euclid TechLabs LLC acknowledges support from the DOE SBIR program, grant No. DE-SC0009572. To create high current, long lasting electron sources capable of providing sub-ps bunches, new photocathode concepts are sought. Most recently, plasmonic nanostructured metal surfaces or flat metal surfaces activated by an ultrathin MgO are under great attention. We report on a photocathode design combining these two approaches. It consists of plasmonic Ag nanoparticles (NPs) functionalized by 3 MgO monolayers (MLs). Ag NPs were synthesized by an aerosol method and MgO was grown by atomic layer deposition (ALD). The NPs geometry was tuned to obtain broadband >50% absorption in the entire blue range as evidenced by UV-vis. spectroscopy. The WF of 3 MgO MLs/Ag NPs multilayer was reduced by 1 eV compared to bare NPs, from 5 to 4 eV, as evidenced by UPS and Kelvin probe. Reduction by 1 eV is maximal for this pair of materials, and agrees well with experimental and theoretical findings. While the effect on WF is indeed significant, a special handling protocol for Ag before depositing MgO is a must. It would preserve a clean Ag surface with a WF of nearly 4 eV to achieve 3 eV upon ALD of MgO. This and other issues are under study to promote photocathode applications.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI058
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WEPRO006	Beam-driven Terahertz Source based on Open Ended Waveguide with a Dielectric Layer	1949
	A.V. Tyukhtin, S.N. Galyamin, V.V. Vorobev Saint-Petersburg State University, Saint-Petersburg, Russia S.P. Antipov Euclid TechLabs, LLC, Solon, Ohio, USA S. Baturin LETI, Saint-Petersburg, Russia
	Funding: Work is supported by the Grant of the President of Russian Federation (MK-273.2013.2) and the Russian Foundation for Basic Research (Grant No. 12-02-31258). Electromagnetic waves with frequencies from 0.1 THz to 10 THz (usually called the Terahertz gap) are of great importance for a number of scientific and practical applications. Different techniques are known allowing generating these frequencies. However, a current trend of physics and industry is to fill this gap with more powerful and efficient sources. For example, recent experiments have shown promising THz generation in dielectric loaded structures. Developing this area, we consider the THz emitting scheme where an ultrarelativistic charge exits the open end of a cylindrical waveguide with a dielectric layer and produces THz waves in a form of Cherenkov radiation. The end of the waveguide is supposed to be either orthogonal to the structure axis or skewed. To obtain THz frequencies from waveguides with centimeter or millimeter radii, we consider high order modes. We present typical field patterns (in the Fraunhofer zone) and show that the aperture of the vacuum channel gives, as a rule, the main contribution. We also give simple expressions for the angle of the main pattern lobe. S. Antipov et al., Appl. Phys. Lett. 100, 132910 (2012).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO006
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WEPRO118	THz Radiation Generation in Multimode Wakefield Structures	2248
	S.P. Antipov, S.V. Baryshev, C.-J. Jing, A. Kanareykin, P. Schoessow Euclid TechLabs, LLC, Solon, Ohio, USA M.G. Fedurin BNL, Upton, Long Island, New York, USA W. Gai, A. Zholents ANL, Argonne, Ilinois, USA D. Wang TUB, Beijing, People's Republic of China
	Funding: DOE SBIR A number of methods for producing sub-picosecond electron bunches have been demonstrated in recent years. A train of these bunches is capable of generating THz radiation via multiple mechanisms like transition, Cherenkov and undulator radiation. We propose to use a bunch train like this to selectively excite a high order mode in a dielectric wakefield structure. This allows us to use wakefield structures that are geometrically larger and easier to fabricate for beam-based THz generation. In this paper we present a THz source design based on this concept and experimental progress to date.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO118
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Paper

Title

Page

The Argonne Wakefield Accelerator (AWA): Commissioning and Operation

1503

M.E. Conde, S.P. Antipov, D.S. Doran, W. Gai, C.-J. Jing, C. Li, W. Liu, J.G. Power, J.Q. Qiu, J.H. Shao, C. Whiteford, E.E. Wisniewski
ANL, Argonne, Illinois, USA
S.P. Antipov, C.-J. Jing, J.Q. Qiu
Euclid TechLabs, LLC, Solon, Ohio, USA
S. Cao
IMP, Lanzhou, People's Republic of China
C. Li, J.H. Shao
TUB, Beijing, People's Republic of China
E.E. Wisniewski
Illinois Institute of Technology, Chicago, Illinois, USA

Funding: Work supported by the U.S. Department of Energy under contract No. DE-AC02-06CH11357.
The commissioning of the upgraded AWA facility is well underway. The new L-band electron gun has been fully commissioned and has been successfully operated with its Cesium Telluride photocathode at a gradient of 80 MV/m. Single bunches of up to 100 nC, and bunch trains of four bunches with up to 80 nC per bunch have been generated. The six new accelerating cavities (L-band, seven cells, pi mode) have been RF conditioned to 12 MW or more; their operation at 10 MW brings the beam energy up to 75 MeV. Measurements of the beam parameters are presently underway, and the use of this intense beam to drive high gradient wakefields will soon follow. One of the main goals of the facility is to generate RF pulses with GW power levels, corresponding to accelerating gradients of hundreds of MV/m and energy gains on the order of 100 MeV per structure.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPME058

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MOPRI058

Metal Plasmonic Nanostructures Functionalized by Atomic Layer Deposition of MgO for Photocathode Applications

739

S.V. Baryshev, S.P. Antipov, A. Kanareykin
Euclid TechLabs, LLC, Solon, Ohio, USA
M.R. Savina, A.V. Zinovev
ANL, Argonne, Illinois, USA
E. Thimsen
University of Minnesota, Minneapolis, USA

Funding: Euclid TechLabs LLC acknowledges support from the DOE SBIR program, grant No. DE-SC0009572.
To create high current, long lasting electron sources capable of providing sub-ps bunches, new photocathode concepts are sought. Most recently, plasmonic nanostructured metal surfaces or flat metal surfaces activated by an ultrathin MgO are under great attention. We report on a photocathode design combining these two approaches. It consists of plasmonic Ag nanoparticles (NPs) functionalized by 3 MgO monolayers (MLs). Ag NPs were synthesized by an aerosol method and MgO was grown by atomic layer deposition (ALD). The NPs geometry was tuned to obtain broadband >50% absorption in the entire blue range as evidenced by UV-vis. spectroscopy. The WF of 3 MgO MLs/Ag NPs multilayer was reduced by 1 eV compared to bare NPs, from 5 to 4 eV, as evidenced by UPS and Kelvin probe. Reduction by 1 eV is maximal for this pair of materials, and agrees well with experimental and theoretical findings. While the effect on WF is indeed significant, a special handling protocol for Ag before depositing MgO is a must. It would preserve a clean Ag surface with a WF of nearly 4 eV to achieve 3 eV upon ALD of MgO. This and other issues are under study to promote photocathode applications.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI058

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WEPRO006

Beam-driven Terahertz Source based on Open Ended Waveguide with a Dielectric Layer

1949

A.V. Tyukhtin, S.N. Galyamin, V.V. Vorobev
Saint-Petersburg State University, Saint-Petersburg, Russia
S.P. Antipov
Euclid TechLabs, LLC, Solon, Ohio, USA
S. Baturin
LETI, Saint-Petersburg, Russia

Funding: Work is supported by the Grant of the President of Russian Federation (MK-273.2013.2) and the Russian Foundation for Basic Research (Grant No. 12-02-31258).
Electromagnetic waves with frequencies from 0.1 THz to 10 THz (usually called the Terahertz gap) are of great importance for a number of scientific and practical applications. Different techniques are known allowing generating these frequencies. However, a current trend of physics and industry is to fill this gap with more powerful and efficient sources. For example, recent experiments have shown promising THz generation in dielectric loaded structures*. Developing this area, we consider the THz emitting scheme where an ultrarelativistic charge exits the open end of a cylindrical waveguide with a dielectric layer and produces THz waves in a form of Cherenkov radiation. The end of the waveguide is supposed to be either orthogonal to the structure axis or skewed. To obtain THz frequencies from waveguides with centimeter or millimeter radii, we consider high order modes. We present typical field patterns (in the Fraunhofer zone) and show that the aperture of the vacuum channel gives, as a rule, the main contribution. We also give simple expressions for the angle of the main pattern lobe.
* S. Antipov et al., Appl. Phys. Lett. 100, 132910 (2012).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO006

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WEPRO118

THz Radiation Generation in Multimode Wakefield Structures

2248

S.P. Antipov, S.V. Baryshev, C.-J. Jing, A. Kanareykin, P. Schoessow
Euclid TechLabs, LLC, Solon, Ohio, USA
M.G. Fedurin
BNL, Upton, Long Island, New York, USA
W. Gai, A. Zholents
ANL, Argonne, Ilinois, USA
D. Wang
TUB, Beijing, People's Republic of China

Funding: DOE SBIR
A number of methods for producing sub-picosecond electron bunches have been demonstrated in recent years. A train of these bunches is capable of generating THz radiation via multiple mechanisms like transition, Cherenkov and undulator radiation. We propose to use a bunch train like this to selectively excite a high order mode in a dielectric wakefield structure. This allows us to use wakefield structures that are geometrically larger and easier to fabricate for beam-based THz generation. In this paper we present a THz source design based on this concept and experimental progress to date.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO118

Export •

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