1 / 48

Energy deposition

nuclear, elastic energy deposition. Ionising energy deposition. Energy deposition. Radiation-induced material modifications. Lattice. Electrons. Small linear regime. Frenkel-pair creation linear cascades. Classical radiolysis. Perturbation. Strong non -linear regime.

mairi
Download Presentation

Energy deposition

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. nuclear, elastic energy deposition Ionising energy deposition Energy deposition Radiation-induced material modifications Lattice Electrons Small linear regime Frenkel-pair creation linear cascades Classical radiolysis Perturbation Strong non -linear regime High LET effects Tracks regime Non-linear cascades Synergy?

  2. ! Nuclear reactions The displacement spectrum Abromeit C. JNM 216 (1994) 78 Nuclear reactions elastic V. M Agramovich and V; V; Kirsanov Physics of rad effects in crystals R. A. Johnson and A; N Orlov Eds. N-H 1986

  3. T > The cascades: the mean free path TRIM (Å) Averback R. S. JNM 216 (1994) 49

  4. Sub-cascades One dense cascade Cascades sub-cascades Linear-non linear Linear All the atoms in movement collide with atoms at rest dpa makes sense Non-linear Atoms in movement collide together collective motion of atoms local melting shock-wave generation

  5. Low T, high T1/2 z = “resistivity” defect/ “Kinchin and Pease”dpa Recombinations: one dpa is not a defect Low T, low T1/2 Exemple : Cu sd 140 barns n0 135 volumes atomiques sr 4000 barns High T Radiation-enhanced diffusion Transient and stationary regimes Influence of: permanent sinks flux Averback R. S. JNM 216 (1994) 49

  6. 0.3 ps 0.62 ps 3.2 ps 0.1 ps 5 ps 11.5 ps 0.5 ps 1 ps 2 ps 6 ps 17.7 ps 23 ps Recombinations: cascades NiAl Au PKA 10 keV Averback R. S. JNM 216 (1994) 49

  7. Inelastic damage

  8. What happens to the projectile Stopping power range stragglings What happens to the solid What happens to: the projectile : secondary particles: electrons recoils

  9. proton on hydrogen proton on aluminium Projectile ion : the atomic processes

  10. Corrections : • Relativistic • Density • Deep levels • Effective charge Projectile ion: the electronic stopping; high velocity Bethe

  11. Projectile ion: the electronic stopping

  12. Projectile: Swift heavy ions Secondary particles: electrons Velocity effect

  13. Projectile: photons electrons Secondary particles: electrons Compton photoelectric

  14. The (dE/dx)e distributions Bragg peak of electrons (dE/dx)e of the projectile over a given thickness Fraction of the dose (dE/dx)e of the secondary electrons (dE/dx)e (keV/µm)

  15. Projectile: low energy heavy ions Secondary particles: recoils The recoils makes the inelastic energy deposition Xe 100keV Projectile: (100 to 50) keV (dE/dx)n≈ 2.5 (dE/dx)e

  16. Radiolysis Low LET Radiolysis is the creation of permanent defects due to the non-radiative recombination of an elementary excitation (a hole-electron pair) The radiolysis yield G Quantum yield This is the “Kinchin and Pease” for inelastic damage

  17. The radiolysis yield G Typical, yields (could be zero) Organic: a few 10-7 mol/J alkali halides (10-8 to 10-9) mol/J 100 eV 1 – 10 keV The yield concept is never use for elastic damage If one dpa = one defect (z=1) For ions (7 10-8 to 1.5 10-7) mol/J

  18. The low LET radiolysis conditions The available energy, Egap (in fact Ex < Egap) > the formation energy of the Frenkel pair. the radiolysis can only occurs in insulators or wide band-gap semiconductors. The excitation must be localised on one atomic (or molecular) site Non-radiative transitions, allowing an efficient kinetic energy transfer to an atom, must prevail over radiative transitions

  19. Could work in alkali halides (anions and cations) alkaline-earth halides Difficult in oxides Frenkel cation Egap Ex Frenkel anion

  20. Low LET radiolysis versus ballistic damage • Radiolysis is not universal, not easily predictable • 2) Is in essence temperature dependent • 3) Spans over a wide time scale • 4) Occurs generally on one sub-lattice (anions) • 5) Radiolysis occurs occasionally • when it occurs, it is with a good energetic efficiency. Elastic damage occurs every time • but with a relatively poor energetic efficiency.

  21. STE: Se et chalcogenides STE: BeO-YAG MgO, Al2O3 Charge-carriers self-trapping Self trapping of charge carriers results from a competition between deformation and polarisation of the lattice

  22. STE Self trapped holes AgCl AgCl KCl KCl CaF2 CaF2 c-SiO2

  23. STE Luminescence STE have several luminescence states a strong Stokes shift very variable lifetime: ns to ms

  24. STE-defect conversion

  25. Correlation - anticorrelation STE luminescence and defect creation Correlation conversion thermal STE triplet -> F +H small S/D

  26. Temporal dynamics Elastic damage : 25 keV Cu cascade over at 10 ps only numerical simulations Radiolysis: fast processes (ps) charge-carrier trapping conversion from STE highly excited stated slow processes (µs to ms) from STE triplet states Also measurements!! metastable defects

  27. Conversion STE-defects a-SiO2 Transient defects c-SiO2 Also in SrTiO3, MgO, Al2O3

  28. Resistant and sensitive materials Resistant: Metals, semi-conductors. crystalline Oxides. c-SiO2 (flux) NaAlSi3O8 : metastables (SrTiO3, MgO, Al2O3, c-SiO2) Sensitive: Alkali halides Alkaline-earth halides CaF2, MgF2,SrF2 : Gmeta , Gstable very low KMgF3, BaF1.1B 0.9, AlF3 (flux?), LiYF4: may be Silver halides AgCl; AgBr Amorphous solids a-SiO2 , a-As2Se3, a-As2S3, a-Se, a-As Water and organic mater (bio matter)

  29. nuclear, elastic energy deposition Ionising energy deposition Energy deposition Radiation-induced material modifications Lattice Electrons Small linear regime Frenkel-pair creation linear cascades Classical radiolysis Perturbation Strong non -linear regime High LET effects Tracks regime Non-linear cascades Synergy?

  30. “Classical” track formation in insulators MICA YIG LET threshold Amorphisation fluctuations critical size induced stress S. Bouffard et al. Phil. Mag. A 81 (2001) 2841 M. Toulemonde, F. Studer Phil. Mag. A 58 (1988) 799 Etching of the amorphous core GSI image Nanotechonology (ITT) M. Toulemonde et al. J. Appl Phys. 68 (1990) 1545

  31. ZrO2 Less common High LET effects Crystal to crystal transformations can exist monoclinic-> tetragonal Two process (incubation fluence)

  32. Unexpected High LET effects Some metals are sensitive to high LET radiation High Tc superconductors are sensitive to high LET radiation (pinning of vortices)

  33. Unexpected High LET effects Plastic instability of amorphous materials: the hammering effect Co75Si15B10 1.7 1013 Xe/cm2; 2.8 MeV/A; 50K Klaumünzer et al. Mat. Res. Proc. 93 (1987) 21 Ion-aligned nanoparticle elongation sample implanted at 1 · 1017 Co/cm2 at 873 K and irradiated at (a) 1013, (b) 3 · 1013, (c) 6 · 1013 and (d) 1014 I/cm2. D'Orleans-C; Stouter-JP; Estournes-C; Grab-JJ; Muller-D; Guille-JL; Richard-Plouet-M; Cerruti-C; Haas-FNIM B 216: 372-8 2004 PHYSICAL REVIEW B 67, 220101 (2003) Fragmentation and grain rotation in NiO single crystals (Klaumuenzer REI-2007) Polygonisation (UO2, CaF2)

  34. Cargèse Bibliography Summer schools The French summer school “Materials Under Irradiation”, Giens 1991, Trans Tech Publications, 1992 (in English) The USA summer school “Fundamentals of Radiation Damage”, Urbana in 1993, J. Nucl. Mat., volume 216 (1994) The French summer schools Lalonde les Maures 1999 et 2000, 2007 (PAMIR) Not published, but printed material (in French)

  35. Bibliography Classics Chr. Lehmann, Interaction of Radiation with Solids and Elementary Defect Production, Series on Defects in Crystalline solids, vol. 10. North-Holland, 1977 N. Nastasi, J. W. Mayer and J. K. Hirvonen, Ion-Solid Interaction, Fundamentals and Applications Cambridge Solid State Science Series, 1996 R. A. Johnson and A. N. Orlov Eds Physics of Radiation Effects in Crystals, North-Holland, 1986 Specific to radiolysis N. Itoh and A. M. Stoneham Material Modification by Electronic Excitation, Cambridge University Press, 2001

  36. Projectile: electron capture Very very slow HCI H. Kurtz et al, Phys. Rev. A49 (1994) 4693 proton on hydrogen

  37. Bibliography Never go to the beach without a good book More specific to radiolysis N. Itoh and A. M. Stoneham Material Modification by Electronic Excitation, Cambridge University Press, 2001 F. Agullo-Lopez, C. R. A. Catlow, P. D. Townsend Point defects in materials Academic Press 1988 N. Itoh ed Defects Processes induced by electronic excitation in insulators World Scientific 1989 K. S. Song, R. T. Williams Self-trapped excitons Springer-Verlag 1993 P. D. Townsend, P. J. Chandler, L. Zhang Optical effects of ion implantation Cambridge 1994

  38. rF ~ 1 µW.cm / % defect Low T, low T1/2 Exemple : Cu sd 140 barns n0 135 volumes atomiques sr 4000 barns J. Dural et al, J. de Physique 38 (1977) 1007

  39. The (dE/dx)e distributions Bragg peak of electrons (dE/dx)e of the projectile over a given thickness Fraction of the dose (dE/dx)e of the secondary electrons (dE/dx)e (keV/µm)

  40. Low LET radiolysis: organics; water The primary species Fragmentation of H2O+ Fragmentation of H2O* Up to 60 reactions < 10-12 s 10-12 s < blobs and short tracks < 10-7 s in bulk >10-7 s Distances empirically

  41. Low LET radiolysis: only role of heterogeneity

  42. Low LET radiolysis: specific role; multi-ionisation Double ionisation and superoxide OOH° Ar C H Gervais-B; Beuve-M; Oliver-GH; Galassi-MERadiation-Physics-and-Chemistry. 2006; 75(4): 493-513

  43. blobs spurs E de 100 à 500 eV E<100 eV Primary electron Annex track Short track E> 5000 eV E< 5000 eV Projectile: photons electrons Secondary particles: electrons

  44. Luminescence quenching

More Related