TY  - JOUR
AU  - Motapothula, Mallikarjuna Rao
AU  - Petrović, Srđan M.
AU  - Nešković, Nebojša B.
AU  - Breese, Mark B.H.
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1205
AB  - Sub-Angstrom focusing of megaelectronvolt (MeV) ions within axial channels was predicted over 10 years ago, but evidence proved elusive. We present experimental angular distributions of axially channeled MeV protons in a 55-nm-thick (001) silicon membrane through which multiple scattering is negligible. Fine angular structure is in excellent agreement with Monte Carlo simulations based on three interaction potentials, providing indirect evidence of the existence of the superfocusing effect with flux enhancement of around 800 within a focused beam width of similar to 20 pm.
T2  - Physical Review B: Condensed Matter and Materials Physics
T1  - Experimental evidence of the superfocusing effect for axially channeled MeV protons
VL  - 94
IS  - 7
DO  - 10.1103/PhysRevB.94.075415
ER  - 

@article{
author = "Motapothula, Mallikarjuna Rao and Petrović, Srđan M. and Nešković, Nebojša B. and Breese, Mark B.H.",
year = "2016",
abstract = "Sub-Angstrom focusing of megaelectronvolt (MeV) ions within axial channels was predicted over 10 years ago, but evidence proved elusive. We present experimental angular distributions of axially channeled MeV protons in a 55-nm-thick (001) silicon membrane through which multiple scattering is negligible. Fine angular structure is in excellent agreement with Monte Carlo simulations based on three interaction potentials, providing indirect evidence of the existence of the superfocusing effect with flux enhancement of around 800 within a focused beam width of similar to 20 pm.",
journal = "Physical Review B: Condensed Matter and Materials Physics",
title = "Experimental evidence of the superfocusing effect for axially channeled MeV protons",
volume = "94",
number = "7",
doi = "10.1103/PhysRevB.94.075415"
}

Motapothula, M. R., Petrović, S. M., Nešković, N. B.,& Breese, M. B.H.. (2016). Experimental evidence of the superfocusing effect for axially channeled MeV protons. in Physical Review B: Condensed Matter and Materials Physics, 94(7).
https://doi.org/10.1103/PhysRevB.94.075415

Motapothula MR, Petrović SM, Nešković NB, Breese MB. Experimental evidence of the superfocusing effect for axially channeled MeV protons. in Physical Review B: Condensed Matter and Materials Physics. 2016;94(7).
doi:10.1103/PhysRevB.94.075415 .

Motapothula, Mallikarjuna Rao, Petrović, Srđan M., Nešković, Nebojša B., Breese, Mark B.H., "Experimental evidence of the superfocusing effect for axially channeled MeV protons" in Physical Review B: Condensed Matter and Materials Physics, 94, no. 7 (2016),
https://doi.org/10.1103/PhysRevB.94.075415 . .

TY  - JOUR
AU  - Petrović, Srđan M.
AU  - Nešković, Nebojša B.
AU  - Ćosić, Marko
AU  - Motapothula, Mallikarjuna Rao
AU  - Breese, Mark B.H.
PY  - 2015
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/752
AB  - This study provides a way to produce very accurate ion atom interaction potentials. We present the high-resolution measurements of angular distributions of protons of energies between 2.0 and 0.7 MeV channeled in a 55 nm thick (0 0 1) silicon membrane. Analysis is performed using the theory of crystal rainbows in which the Molieres interaction potential is modified to make it accurate both close to the channel axis and close to the atomic strings defining the channel. This modification is based on adjusting the shapes of the rainbow lines appearing in the transmission angle plane, with the resulting theoretical angular distributions of transmitted protons being in excellent agreement with the corresponding experimental distributions.
T2  - Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms
T1  - Proton-silicon interaction potential extracted from high-resolution measurements of crystal rainbows
VL  - 360
SP  - 23
EP  - 29
DO  - 10.1016/j.nimb.2015.07.104
ER  - 

@article{
author = "Petrović, Srđan M. and Nešković, Nebojša B. and Ćosić, Marko and Motapothula, Mallikarjuna Rao and Breese, Mark B.H.",
year = "2015",
abstract = "This study provides a way to produce very accurate ion atom interaction potentials. We present the high-resolution measurements of angular distributions of protons of energies between 2.0 and 0.7 MeV channeled in a 55 nm thick (0 0 1) silicon membrane. Analysis is performed using the theory of crystal rainbows in which the Molieres interaction potential is modified to make it accurate both close to the channel axis and close to the atomic strings defining the channel. This modification is based on adjusting the shapes of the rainbow lines appearing in the transmission angle plane, with the resulting theoretical angular distributions of transmitted protons being in excellent agreement with the corresponding experimental distributions.",
journal = "Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms",
title = "Proton-silicon interaction potential extracted from high-resolution measurements of crystal rainbows",
volume = "360",
pages = "23-29",
doi = "10.1016/j.nimb.2015.07.104"
}

Petrović, S. M., Nešković, N. B., Ćosić, M., Motapothula, M. R.,& Breese, M. B.H.. (2015). Proton-silicon interaction potential extracted from high-resolution measurements of crystal rainbows. in Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms, 360, 23-29.
https://doi.org/10.1016/j.nimb.2015.07.104

Petrović SM, Nešković NB, Ćosić M, Motapothula MR, Breese MB. Proton-silicon interaction potential extracted from high-resolution measurements of crystal rainbows. in Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. 2015;360:23-29.
doi:10.1016/j.nimb.2015.07.104 .

Petrović, Srđan M., Nešković, Nebojša B., Ćosić, Marko, Motapothula, Mallikarjuna Rao, Breese, Mark B.H., "Proton-silicon interaction potential extracted from high-resolution measurements of crystal rainbows" in Nuclear Instruments and Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms, 360 (2015):23-29,
https://doi.org/10.1016/j.nimb.2015.07.104 . .

TY  - JOUR
AU  - Motapothula, Mallikarjuna Rao
AU  - Petrović, Srđan M.
AU  - Nešković, Nebojša B.
AU  - Dang, Z. Y.
AU  - Breese, Mark B.H.
AU  - Rana, Mukhtar Ahmed
AU  - Osman, A.
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5177
AB  - Using the theory of crystal rainbows, we prove that the well-known doughnut patterns observed in ion channeling in thin crystal membranes are manifestations of the rainbow effect. This is done by a detailed morphological study of the high-resolution experimental angular distributions of 2 MeV protons channeled in a 55-nm-thick (001) silicon crystal tilted away from the [001] direction. The inner side of the doughnut is the dark side of the rainbow, analogous to the Alexanders dark band, occurring between the primary and secondary meteorological rainbows.
T2  - Physical Review B: Condensed Matter and Materials Physics
T1  - Origin of ringlike angular distributions observed in rainbow channeling in ultrathin crystals
VL  - 86
IS  - 20
DO  - 10.1103/PhysRevB.86.205426
ER  - 

@article{
author = "Motapothula, Mallikarjuna Rao and Petrović, Srđan M. and Nešković, Nebojša B. and Dang, Z. Y. and Breese, Mark B.H. and Rana, Mukhtar Ahmed and Osman, A.",
year = "2012",
abstract = "Using the theory of crystal rainbows, we prove that the well-known doughnut patterns observed in ion channeling in thin crystal membranes are manifestations of the rainbow effect. This is done by a detailed morphological study of the high-resolution experimental angular distributions of 2 MeV protons channeled in a 55-nm-thick (001) silicon crystal tilted away from the [001] direction. The inner side of the doughnut is the dark side of the rainbow, analogous to the Alexanders dark band, occurring between the primary and secondary meteorological rainbows.",
journal = "Physical Review B: Condensed Matter and Materials Physics",
title = "Origin of ringlike angular distributions observed in rainbow channeling in ultrathin crystals",
volume = "86",
number = "20",
doi = "10.1103/PhysRevB.86.205426"
}

Motapothula, M. R., Petrović, S. M., Nešković, N. B., Dang, Z. Y., Breese, M. B.H., Rana, M. A.,& Osman, A.. (2012). Origin of ringlike angular distributions observed in rainbow channeling in ultrathin crystals. in Physical Review B: Condensed Matter and Materials Physics, 86(20).
https://doi.org/10.1103/PhysRevB.86.205426

Motapothula MR, Petrović SM, Nešković NB, Dang ZY, Breese MB, Rana MA, Osman A. Origin of ringlike angular distributions observed in rainbow channeling in ultrathin crystals. in Physical Review B: Condensed Matter and Materials Physics. 2012;86(20).
doi:10.1103/PhysRevB.86.205426 .

Motapothula, Mallikarjuna Rao, Petrović, Srđan M., Nešković, Nebojša B., Dang, Z. Y., Breese, Mark B.H., Rana, Mukhtar Ahmed, Osman, A., "Origin of ringlike angular distributions observed in rainbow channeling in ultrathin crystals" in Physical Review B: Condensed Matter and Materials Physics, 86, no. 20 (2012),
https://doi.org/10.1103/PhysRevB.86.205426 . .