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Sergey V. Baryshev

Publications and source records attributed to Sergey V. Baryshev.

40 records · Page 3Linked to original sources
arXiv2014

Planar Ultrananocrystalline Diamond Field Emitter in Accelerator RF Electron Injector: Performance Metrics

A case performance study of a planar field emission cathode (FEC) based on nitrogen-incorporated ultrananocrystalline diamond, (N)UNCD, was carried out in an RF 1.3 GHz electron gun. The FEC was a 100 nm (N)UNCD film grown on a 20 mm diameter stainless steel disk with a Mo buffer layer. At surface gradients 45-65 MV/m, peak currents of 1-80 mA (equivalent to 0.3-25 mA/cm$^2$) were achieved. Imaging with two YAG screens confirmed emission from the (N)UNCD surface with (1) the beam emittance of 1.5 mm$\times$mrad/mm-rms, and (2) longitudinal FWHM and rms energy spread of 0.7% and 11% at an electron energy of 2 MeV. Current stability was tested over the course of 36$\times$10$^3$ RF pulses (equivalent to 288$\times$10$^6$ GHz oscillations).

physics.acc-ph↗
arXiv2014

Enthalpy of formation for Cu-Zn-Sn-S (CZTS)

Herein we report an analytical procedure to calculate the enthalpy of formation for thin film multinary compounds from sputtering rates measured during ion bombardment. The method is based on Sigmund's sputtering theory and the Born-Haber cycle. Using this procedure, an enthalpy of formation for a CZTS film of the composition Cu$_{1.9}$Zn$_{1.5}$Sn$_{0.8}$S$_4$ was measured as -930$\pm$98 kJ/mol. This value is much more negative than the sum of the enthalpies of formation for the constituent binary compounds, meaning the multinary formation reaction is predicted to be exothermic.

cond-mat.mtrl-sci↗
arXiv2012

Hall helps Ohm: some corrections to negative-U centers approach to transport properties of YBa$_2$Cu$_3$O$_x$ and La$_{2-x}$Sr$_x$CuO$_4$

For broad oxygen and strontium doping ranges, temperature dependences (T-dependences) of the normal state resistivity ρ(T) of YBa_2Cu_3O_x (YBCO) and La_(2-x)Sr_xCuO_4 (LSCO) are calculated and compared to experiments. Holes transport was taken in the τ-approximation, where τ(T,ε) is due to acoustic phonons. Besides, T-dependence of the chemical potential μ(T) and effective carrier mass m* ~10-100 free electron masses, obtained by negative-U centers modelling the T-dependence of the Hall coefficient, were used to calculate ρ(T). In addition, it is demonstrated that anisotropy of the cuprates does not affect the calculated T-variation of neither Hall coefficient nor ρ, but only rescale their magnitudes by factors depending on combinations of m_ab and m_c.

cond-mat.supr-con↗