TITLE

Effect of n+GaN cap polarization field on Cs-free GaN photocathode characteristics

AUTHOR(S)
Tripathi, N.; Bell, L. D.; Nikzad, S.; Shahedipour-Sandvik, F.
PUB. DATE
August 2010
SOURCE
Applied Physics Letters;8/2/2010, Vol. 97 Issue 5, p052107
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We report on a Cs-free GaN photocathode structure in which band engineering at the photocathode surface caused by Si delta doping eliminates the need for use of cesium for photocathode activation. The structure is capped with a highly doped n+GaN layer. We have identified that n+GaN cap thickness plays an important role in limiting the effect of polarization induced charges at the GaN surface on the photocathode emission threshold. Physics based device simulations is used for further analysis of the experimental results. Our findings clearly illustrate the impact of polarization induced surface charges on the device properties including its emission threshold.
ACCESSION #
52802616

 

Related Articles

  • High Performance AlInGaAs/AlGaAs Photocathode. Mamaev, Yu. A.; Gerchikov, L. G.; Yashin, Yu. P.; Vasiliev, D. A.; Kuzmichev, V. V.; Ustinov, V. M.; Zhukov, A. E.; Mikhrin, V. S. // AIP Conference Proceedings;2/6/2008, Vol. 980 Issue 1, p85 

    New photocathode for highly polarized electron emission has been developed, fabricated and studied. Polarized electron source is based on short-period strained AlInGaAs/AlGaAs superlattice grown by MBE method. Deformation of AlInGaAs quantum well results in 85 meV energy splitting between heavy...

  • Hybrid ion acceleration with ultrathin composite foils irradiated by high intensity circularly-polarized laser light. Andreev, A. A.; Steinke, S.; Schnuerer, M.; Henig, A.; Nickles, P. V.; Platonov, K. Y.; Sokollik, T.; Sandner, W. // Physics of Plasmas;Dec2010, Vol. 17 Issue 12, p123111 

    A complete analytical description of ion acceleration in the laser radiation-pressure regime is presented. The combined effects of hot electron and light-pressure phenomena are used to qualitatively and quantitatively describe most recent experimental results in this regime. An essential part of...

  • High-quality proton bunch from laser interaction with a gas-filled cone target. Wang, H. Y.; Lin, C.; Zheng, F. L.; Lu, Y. R.; Guo, Z. Y.; He, X. T.; Chen, J. E.; Yan, X. Q. // Physics of Plasmas;Sep2011, Vol. 18 Issue 9, p093105 

    Generation of high-energy proton bunch from interaction of an intense short circularly polarized (CP) laser pulse with a gas-filled cone target (GCT) is investigated using two-dimensional particle-in-cell simulation. The GCT target consists of a hollow cone filled with near-critical gas-plasma...

  • High brightness and high polarization electron source using transmission photocathode with GaAs-GaAsP superlattice layers. Yamamoto, Naoto; Nakanishi, Tsutomu; Mano, Atsushi; Nakagawa, Yasuhide; Okumi, Shoji; Yamamoto, Masahiro; Konomi, Taro; Xiuguang Jin; Ujihara, Toru; Takeda, Yoshikazu; Ohshima, Takashi; Saka, Takashi; Kato, Toshihiro; Horinaka, Hiromichi; Yasue, Tsuneo; Koshikawa, Takanori; Kuwahara, Makoto // Journal of Applied Physics;Mar2008, Vol. 103 Issue 6, p064905 

    In order to produce a high brightness and high spin polarization electron beam, a pointlike emission mechanism is required for the photocathode of a GaAs polarized electron source. For this purpose, the laser spot size on the photocathode must be minimized, which is realized by changing the...

  • High Brightness and high polarization electron source using transmission photocathode. Yamamoto, Naoto; Xiuguang Jin; Mano, Atsushi; Nakagawa, Yasuhide; Nakanishi, Tsutomu; Ujihara, Toru; Okumi, Shoji; Yamamoto, Masahiro; Konomi, Taro; Takeda, Yoshikazu; Ohshima, Takashi; Saka, Takashi; Kato, Toshihiro; Horinaka, Hiromichi; Yasue, Tsuneo; Koshikawa, Takanori // AIP Conference Proceedings;8/4/2009, Vol. 1149 Issue 1, p1052 

    A transmission photocathode was fabricated based on GaAs-GaAsP strained superlattice layers on a GaP substrate and a 20 kV-gun was built to generate the polarized electron beams with the diameter of a few micro-meter. As the results, the reduced brightness of 1.3×107 A/cm2/sr and the...

  • Superlattice Photocathode with High Brightness and Long NEA-Surface Lifetime. Nishitani, Tomohiro; Tabuchi, Masao; Takeda, Yoshikazu; Suzuki, Yuji; Motoki, Kazuya; Meguro, Takashi // AIP Conference Proceedings;8/4/2009, Vol. 1149 Issue 1, p1047 

    We have suggested that a small momentum spread of photoelectrons and high quantum efficiency can be obtained concurrently by a photocathode using a semiconductor with a superlattice instead of a bulk. We have begun to search for the suitable semiconductor material of a superlattice photocathode...

  • MBE Growth of Graded Structures for Polarized Electron Emitters. Moy, Aaron; Maruyama, T.; Zhou, F.; Brachmann, A. // AIP Conference Proceedings;8/4/2009, Vol. 1149 Issue 1, p1038 

    SVT Associates, in collaboration with SLAC, has investigated two novel photocathode design concepts in an effort to increase polarization and quantum efficiency. AlGaAsSb/GaAs superlattice photocathodes were fabricated to explore the effect of antimony on device operation. In the second...

  • Λ[sup 0] Polarization in pp→p{Λ[sup 0]K[sup +]} at 800 GeV/c. Fe´lix, J.; Berisso, M. C.; Christian, D. C.; Gara, A.; Gottschalk, E. E.; Gutierrez, G.; Hartouni, E. P.; Knapp, B. C.; Kreisler, M. N.; Lee, S.; Markianos, K.; Moreno, G.; Reyes, M. A.; Sosa, M.; Wang, M. H. L. S.; Wehmann, A.; Wesson, D. // AIP Conference Proceedings;2000, Vol. 531 Issue 1, p381 

    We present some preliminary measurements of Λ[sup 0] polarization, in the final state pp → p{Λ[sup 0]K[sup +]) created at 800 GeV/c, as a function of P[sub T], x[sub F], and the diffractive mass of the object {Λ[sup 0]K[sup +]}.

  • Status of Frozen-spin Polarized HD Targets for Spin Experiments. Kageya, Tsuneo; Bade, Christopher M.; Caracappa, Anthony; Lincoln, Frank C.; Lowry, Michael M.; Mahon, John C.; Miceli, Lino; Sandorfi, Andrew M.; Thorn, Craig E.; Xiadong Wei, Craig E.; Whisnant, C. Steven // AIP Conference Proceedings;2003, Vol. 675 Issue 1, p857 

    The first experiments have been carried out with polarized HD targets at the Laser-Electron-Gamma-Source (LEGS) facility. By holding targets at low temperature and high field (17 mK and 15 Tesla) in a Dilution Refrigerator (DF) for six weeks a frozen-spin state was reached, with equilibrium...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics