A. Orecchini - T-REX, a chopper spectrometer for magnetism

T-REX
Time-of-flight Reciprocal space Explorer
A chopper spectrometer for magnetism, material
science and soft matter at ESS
Andrea Orecchini
Dipartimento di Fisica e Geologia, Università degli Studi di Perugia
European Spallation Source
(Lund, Svezia)
• Sorgente impulsata di neutroni di nuova generazione
• Maggiore brillanza
• Nuove opportunità scientifiche e tecnologiche
The long neutron pulse of ESS
14 Hz
European Spallation Source
(Lund, Svezia)
Protons
Neutrons
European Spallation Source
(Lund, Svezia)
European Spallation Source
(Lund, Svezia)
T-REX
German-Italian collaboration
Jülich Center for Neutron Science
(Germany)
Thomas
Brückel
Jörg
Voigt
Università degli Studi di Perugia
(Italy)
Francesco
Sacchetti
Nicolò
Violini
~75%
Earl
Babcock
Zahir
Sahli
~25%
Marco
Zanatta
Andrea
Orecchini
Alessandro
Paciaroni
T-REX
A classic “Time-of-Flight” spectrometer:
• neutron guide (165 m)
• T0 and disk choppers (1+7)
• sample chamber + flight chamber
• position-sensitive detector
• shielding
Elements of novelty:
• Multichromatic beam (RRM)
• Polarization Analysis (spin)
Time-Distance diagram
(multicromatic beam)
λ (Å)
Dynamical Range
Main features
Gain factors
Science Cases
Incident
Neutron
Energy
0 meV
C-SPEC:
high
resolution
T-REX:
polarization
dyn. range
VOR:
overview
time dep.
CAMEA:
extreme
conditions
QENS, Soft Matter, Life Science
60 meV
Low-D magnets
nonchiral-,
equilibrium
frustrated,
physics
nanomagnets
energy materials
correlated
electron
systems
150 meV
phonons
&
DOS
Quantum
phase
transitions
Spin waves in Ba3NbFe3Si2O14 single crystals
• Wide survey on IN5 (ToF) + Polarization Analysis on IN20 (TAS)
• Very good energy resolution
• Good Q resolution
• High flux
Expt. Data
Simulations
Loire et al., PRL 106, 207201 (2011)
Hour-glass magnetic spectrum in La2-xSrxCoO4
• Wide energy range, from 2 to 100 meV
• Phonons at 12 and 25 meV?... Polarization Analysis…
• Wide 4D mapping  Spurions identification
35
30
90
25
20
85
25
20
80
15
10
75
5
Y. Drees et al., Nat. Comm. 4, 2449 (2013)
Blue-shift upon ligand binding in lysozyme
• Small and anisotropic signal from functional vibrations
(2 techniques)
• High flux
• 4D mapping
Frequency (cm-1)
Crystal Angle (degrees)
Turton et al., Nat. Comm. 5, 3999 (2014)
Short-wavelength collective excitations in disordered
materials
• Complex multi-branched dispersion curves
(2 instruments, variable resolution)
• Multichromatic beam!
Zanatta et al., J. Phys. Chem. Lett. 4, 1143 (2013)
• Small signals / small samples
(molecular magnets/nanomagnets)
• High-flux / high resolution
• Wide 4D dynamic range
• Polarization Analysis
(separation of coherent and spin-incoherent signals)
ESS beam lines
A regime:
22 strumenti
T-REX
16 strumenti
valutati ed approvati
da STAP e SAC di ESS
3 avviati
(2014-…)
9 in 1° priorità
(fine 2015-…)
(inizio 2016-…)
4 in 2° priorità
(2017-…)
(2018-…)
Tempistica
(planning ESS)
T-REX : 2015-2023
T-REX
Time-of-flight Reciprocal space Explorer
A chopper spectrometer for magnetism, material
science and soft matter at ESS
Andrea Orecchini
Dipartimento di Fisica e Geologia, Università degli Studi di Perugia
Grazie per l’attenzione!