|
1.
|
Structural formation yield of GeV centers from implanted Ge in diamond
/ Wahl, Ulrich (IST, Lisbon (main)) ; Correia, João Guilherme (IST, Lisbon (main)) ; Costa, Ângelo (Leuven U.) ; Lamelas, Afonso (Aveiro U.) ; Amaral, Vítor (Aveiro U.) ; Johnston, Karl (CERN) ; Magchiels, Goele (Leuven U.) ; Tunhuma, Shandirai Malven (Leuven U.) ; Vantomme, André (Leuven U.) ; Pereira, Lino M C (Leuven U.)
In order to study the structural formation yield of germanium-vacancy (GeV) centers from implanted Ge in diamond, we have investigated its lattice location by using the β$^{−}$ emission channeling technique from the radioactive isotope $^{75}$Ge (t$_{1/2}$ = 83 min) produced at the ISOLDE/CERN facility. $^{75}$Ge was introduced via recoil implantation following 30 keV ion implantation of the precursor isotope $^{75}$Ga (126 s) with fluences around 2 × 10$^{12}$–5 × 10$^{13}$ cm$^{−2}$. [...]
2024 - 16 p.
- Published in : Mat. Quant. Tech. 4 (2024) 025101
Fulltext: PDF;
|
|
|
2.
|
Magnesium-Vacancy Optical Centers in Diamond
/ Corte, Emilio ; Andrini, Greta ; Nieto Hernández, Elena ; Pugliese, Vanna ; Costa, Ângelo ; Magchiels, Goele ; Moens, Janni ; Tunhuma, Shandirai Malven ; Villarreal, Renan ; Pereira, Lino M. C. et al.
We provide the first systematic characterization of the structural and photoluminescence properties of optically active centers fabricated upon implantation of 30–100 keV Mg+ ions in synthetic diamond. The structural configurations of Mg-related defects were studied by the electron emission channeling technique for short-lived, radioactive 27Mg implantations at the CERN-ISOLDE facility, performed both at room temperature and 800 °C, which allowed the identification of a major fraction of Mg atoms (∼30 to 42%) in sites which are compatible with the split-vacancy structure of the MgV complex. [...]
- Published in : ACS Photonics 10 (2023) 101-110
Fulltext: MgV_SupportingInformation - PDF; ACSPhotonics_2023_10_0101 - PDF;
|
|
|
3.
|
FastIC: A Highly Configurable ASIC for Fast Timing Applications
/ Gόmez, S (Barcelona, IEEC) ; Fernández-Tenllado, J M (CERN) ; Alozy, J (CERN) ; Campbell, M (CERN) ; Manera, R (ICC, Barcelona U.) ; Mauricio, J (ICC, Barcelona U.) ; Mariscal, A (ICC, Barcelona U.) ; Pujol, C (ICC, Barcelona U.) ; Sánchez, D (Barcelona, IEEC) ; Sanmukh, A (ICC, Barcelona U.) et al.
This work presents the 8-channel FastIC ASIC developed in CMOS 65 nm technology suitable for the readout of positive and negative polarity sensors with intrinsic amplification in High Energy Physics experiments, Positron Emission Tomography and other Time-of-Flight systems. The front-end can be configured to readout each input channel individually or perform analog summation of up to 4 single-ended channels before discrimination in view of extending precise timing to large and segmented areas. [...]
2021 - 4 p.
- Published in : 10.1109/NSS/MIC44867.2021.9875546
In : IEEE NSS MIC 2021, Online, Japan, 16 - 23 Oct 2021, pp.1-4
|
|
|
4.
|
Direct evidence of Be as an amphoteric dopant in GaN
/ Wahl, U. (IST, Lisbon) ; Correia, J. G. (IST, Lisbon) ; Costa, A. R. G. (KU Leuven) ; Lima, T. A. L. (KU Leuven) ; Moens, J. (KU Leuven) ; Kappers, M. J. (Cambridge U.) ; da Silva, M. R. (Aveiro U., CICECO) ; Pereira, L. M. C. (KU Leuven) ; Vantomme, A. (KU Leuven)
/IS634 Collaboration
The interest in Be as an impurity in GaN stems from the challenge to understand why GaN can be doped p type with Mg, while this does not work for Be. While theory has actually predicted an acceptor level for Be that is shallower than Mg, it was also argued that Be is not a suitable acceptor because its am-photeric nature, i.e. [...]
2022
- Published in : Phys. Rev. B 105 (2022) 184112
Postprint from Phys. Rev. B 105 (2022) 184112: PDF; Supplemental Material from Phys. Rev. B 105 (2022) 184114: PDF;
|
|
|
5.
|
|
|
6.
|
|
|
7.
|
Lattice sites of implanted Na in GaN and AlN in comparison to other light alkalis and alkaline earths
/ Wahl, Ulrich (Universidade de Lisboa (PT)) ; David Bosne, Eric (Universidade de Lisboa (PT)) ; Amorim, Lígia (KU Leuven) ; Granadeiro Costa, Angelo Rafael (Universidade de Lisboa (PT)) ; De Vries, Bart (KU Leuven) ; Martins Correia, Joao (Universidade de Lisboa (PT)) ; da Silva, Manuel Ribeiro (CICECO Aveiro) ; Da Costa Pereira, Lino Miguel (KU Leuven (BE)) ; Vantomme, André (KU Leuven)
/IS634 Collaboration
The lattice location of ion implanted radioactive 24Na (t1/2=14.96 h) in GaN and AlN was determined using the emission channeling technique at the ISOLDE/CERN facility. In the room temperature as-implanted state in both GaN and AlN, the majority of the sodium atoms are found on interstitial sites near the octahedral position, with a minority on cation Ga or Al substitutional sites. [...]
CERN-ISOLDE-2021-003.-
2020 - 12 p.
- Published in : J. Appl. Phys. 128 (2020) 045703
Postprint: PDF; Supplemental Material: PDF;
|
|
|
8.
|
Direct Structural Identification and Quantification of the Split-Vacancy Configuration for Implanted Sn in Diamond
/ Wahl, Ulrich (Universidade de Lisboa (PT)) ; Martins Correia, Joao (Universidade de Lisboa (PT)) ; Villarreal, Renan (KU Leuven) ; Bourgeois, Emilie (Hasselt University) ; Gulka, Michal (Hasselt University) ; Nesladek, Milos (Hasselt University) ; Vantomme, André (KU Leuven) ; Da Costa Pereira, Lino Miguel (KU Leuven (BE))
/EC-SLI Collaboration ; IS368 Collaboration
We demonstrate formation of the ideal split-vacancy configuration of the Sn-vacancy center upon implantation into natural diamond. Using beta-emission channeling following low fluence 121Sn implantation (2E12 atoms/cm2, 60 keV) at the ISOLDE facility at CERN, we directly identified and quantified the atomic configurations of the Sn-related centers. [...]
CERN-ISOLDE-2021-002.-
2020 - 7 p.
- Published in : Phys. Rev. Lett. 125 (2020) 045301
Postprint: PDF; Supplemental material: PDF;
|
|
|
9.
|
|
|
10.
|
Lattice location of implanted transition metals in 3C–SiC
/ Granadeiro Costa, Angelo Rafael (Universidade de Lisboa (PT)) ; Wahl, Ulrich (Universidade de Lisboa (PT)) ; Martins Correia, Joao (Universidade de Lisboa (PT)) ; David Bosne, Eric (Universidade de Lisboa (PT)) ; Amorim, Lígia (KU Leuven (BE)) ; Silva, Daniel (Universidade do Porto (PT)) ; Castro Ribeiro Da Silva, Manuel (Universidade de Lisboa (PT)) ; Bharuth-Ram, Krishanlal (University of Kwazulu - Natal (ZA)) ; Da Costa Pereira, Lino Miguel (KU Leuven (BE))
/EC-SLI Collaboration
We have investigated the lattice location of implanted transition metal (TM) 56Mn, 59Fe and 65Ni ions in undoped single-crystalline cubic 3C–SiC by means of the emission channeling technique using radioactive isotopes produced at the CERN-ISOLDE facility. We find that in the room temperature as-implanted state, most Mn, Fe and Ni atoms occupy carbon-coordinated tetrahedral interstitial sites (TC). [...]
CERN-OPEN-2017-022.-
Lisboa : Instituto Superior Técnico, 2017 - 11 p.
- Published in : J. Phys. D 50 (2017) 215101
Preprint: PDF;
|
|
email alert
or subscribe to the 
RSS feed.