DAFS - Universidad de Zaragoza
DAFS - Universidad de Zaragoza DAFS - Universidad de Zaragoza
Abs II II EXAFS and EDAFS best fit results Abs. Sample→ paths (Å)↓ (As abs -As II ) // (As abs -As II ) ⊥ (As abs -P II ) // (As abs -P II ) ⊥ (As abs -In III ) // (As abs -In III ) ⊥ %P // % P ⊥ II InAs Bulk 4.284 4.284 - - 5.023 5.023 - - As,P In InAs/InP (pseud.) 4.15 4.29 - - 4.87 5.13 - - II shell distances CP1276 (EXAFS e ⊥ & e // ) 4.16±0.06 4.23±0.04 4.19±0.07 4.17±0.03 4.88±0.03 4.93±0.06 0.3±0.1 0.5±0.1 Strain P content CP1276 (DAFS e ⊥ ) - 4.30±0.04 - 4.20±0.06 - - - 0.4±0.2 Pure strained InAs or InAsP alloy ? I3701 (EXAFS e ⊥ & e // ) 4.15±0.06 4.25±0.04 4.15±0.07 4.18±0.03 4.87±0.03 4.94±0.06 0.4±0.1 0.6±0.1 I3701 (DAFS e ⊥ ) - 4.22±0.04 - 4.19±0.06 - - - 0.4±0.3 32/50
EXAFS (ε // & ε ⊥) Similar results for the 2 samples Mixing of two different As environments Strained InAs & InAsP alloy ? Intermixing As/P at the QWrs/capping interface P diffused QWrs Nice example of DAFS spatial selectivity and of strong EXAFS/DAFS complementarity GIDAFS probes the QWrs As atoms (the contribution of each atom depends on Q) EXAFS probes all As atoms EDAFS (ε ⊥) Different results for the 2 samples Different As-As and As-P II shell dist. CP1276: InAs QWrs + As/P intermixing at interface & capping I3701: InAsP QWrs + As/P intermixing at interface & capping 33/50
- Page 1 and 2: Universidad de Zaragoza Curso de Ma
- Page 3 and 4: TÉCNICAS EXPERIMENTALES µ I diff
- Page 5 and 6: EL DAFS El DAFS es la estructura fi
- Page 7 and 8: Resonant atomic scattering factor f
- Page 9 and 10: y 0 Structure factor: Multi-wavelen
- Page 11 and 12: I F diff 0 F 0 Análisis de datos D
- Page 13 and 14: Using the path formalism for descri
- Page 15 and 16: Spatial selectivity : GaAs xP 1-x/G
- Page 17 and 18: TEM InAs/InP QWrs AFM 200nm GaN/AlN
- Page 19 and 20: Local structure study of InAs/InP Q
- Page 21 and 22: As-O As K-edge EXAFS (BM8-ESRF) Int
- Page 23 and 24: Grazing incidence diffraction BM2-D
- Page 25 and 26: GI-DAFS (Grazing Incidence DAFS) k(
- Page 27 and 28: Diffraction Intensity (a.u.) GIDAFS
- Page 29 and 30: Abs II EXAFS and EDAFS best fit res
- Page 31: GIDAFS oscillations analysis CP1276
- Page 35 and 36: Applications : Nanostructures III-V
- Page 37 and 38: Applications : Nanostructures III-V
- Page 39 and 40: BQ GaN/AlN 10ML : EXAFS vs DAFS k
- Page 41 and 42: BQ GaN/AlN : EDAFS simulations h=2.
- Page 43 and 44: Orden de carga y reflexiones prohib
- Page 45 and 46: Estado electrónico de los sitios o
- Page 47 and 48: Anisotropía del factor de dispersi
- Page 49 and 50: Zona del umbral (DANES) Modelo refl
- Page 51 and 52: Prepico Cálculos “ab initio” d
- Page 53: Grazing Incidence Diffraction Anoma
Abs II<br />
II<br />
EXAFS and E<strong>DAFS</strong> best fit results<br />
Abs.<br />
Sample→<br />
paths (Å)↓<br />
(As abs -As II ) //<br />
(As abs -As II ) ⊥<br />
(As abs -P II ) //<br />
(As abs -P II ) ⊥<br />
(As abs -In III ) //<br />
(As abs -In III ) ⊥<br />
%P //<br />
% P ⊥<br />
II<br />
InAs<br />
Bulk<br />
4.284<br />
4.284<br />
-<br />
-<br />
5.023<br />
5.023<br />
-<br />
-<br />
As,P<br />
In<br />
InAs/InP<br />
(pseud.)<br />
4.15<br />
4.29<br />
-<br />
-<br />
4.87<br />
5.13<br />
-<br />
-<br />
II shell<br />
distances<br />
CP1276<br />
(EXAFS e ⊥ & e<br />
// )<br />
4.16±0.06<br />
4.23±0.04<br />
4.19±0.07<br />
4.17±0.03<br />
4.88±0.03<br />
4.93±0.06<br />
0.3±0.1<br />
0.5±0.1<br />
Strain<br />
P content<br />
CP1276<br />
(<strong>DAFS</strong> e ⊥<br />
)<br />
-<br />
4.30±0.04<br />
-<br />
4.20±0.06<br />
-<br />
-<br />
-<br />
0.4±0.2<br />
Pure strained InAs<br />
or<br />
InAsP alloy ?<br />
I3701<br />
(EXAFS e ⊥ & e // )<br />
4.15±0.06<br />
4.25±0.04<br />
4.15±0.07<br />
4.18±0.03<br />
4.87±0.03<br />
4.94±0.06<br />
0.4±0.1<br />
0.6±0.1<br />
I3701<br />
(<strong>DAFS</strong> e ⊥<br />
)<br />
-<br />
4.22±0.04<br />
-<br />
4.19±0.06<br />
-<br />
-<br />
-<br />
0.4±0.3<br />
32/50
Change language