solid state physics program - cern

Solid State Physics Program

Juliana Schell1,2

Doru C. Lupascu2

on behalf of the SSP Community

1 CERN, Geneva, Switzerland2 Institute for Materials Science and Center for Nanointegration

Duisburg-Essen (CENIDE), University of Duisburg-Essen, Germany

ISOLDE Workshop and Users meeting 2016

Nuclear Solid State Physics “Birth”

2ISOLDE Workshop and Users meeting 2016 by Juliana Schell

1920

J. Gróh and G. V. HevesyAnnalen der Physik 1920 vol 368,

issue 17, pages 85-92„Die Selbstdiffusionsgeschwindigkeit

des geschmolzenen Bleis"

1955

P. Lehmann and J. MillerCompt. Rend. Acad. Sc. 1955

vol. 240, pages 298 -299„Interaction quadrupolaire dans

111Cd“

1975

"

H. Haas„First results are described in theHMI-AR/1976. First conferencecontribution: HFI-IV in Madison(1977): 79Kr/Zn,Cd,Sb.

1959

R.L. MössbauerZeitschrift für Naturforschung 1959

vol 14a, pages 211-216„Kernresonanzabsorptionvon γ-Strahlung in Ir191"


PACEFG and BHF, charge

symmetry from 10 to 1500

K

MSEFG and BHF, charge

symmetry, binding

properties

ECLattice location

ASPICVersatile system to study

surfaces and interfaces

DLTSStudy concentration of

electrically active defects

/analyze the content of

deep level defects in the

material

PLOptical and electronic

properties

...and much more!Hall effect, capacity-

voltage, electrical

conductivity, paramagnetic

resonance spectroscopy

DiffusionThermal motion of

particles

Techniques1976-1991


PACGelbPAC

MSUsing LED excitation

EC123Sn

ASPICShipped to KU-Leuven:

upgrade and maintenance

DLTS

PLsummer student project

...and much more!

DiffusionOffline studies

Techniques2016

SSP infraestructure


Annealing roomCollaboration ISOLDE, BMBF,

FCT, KU-Leuven

Digital PACCollaboration ISOLDE, BMBF

SSP infraestructure


Conventional PACCollaboration ISOLDE, BMBF,

FCT

Digital and conventional PACFCT, BMBF, ISOLDE

Emission channelingFCT, KU-Leuven

Upgrades


The new implantation chamber at the GLM

branchBMBF Universität Göttingen

Nagl, Vetter, Hofsäss

Poster: Christoph Pohl

Perturbed Angular Correlations with Short-Lived Isotopes, thePAC-SLI setupPoster: Abel Fenta & Manuel Silva

Emission Channeling with Timepix position sensitive dectectorsPoster: David Bosne

Upgrades: chemical lab


Chemical labCollaboration ISOLDE, BMBF,

FCT, COPENHAGEN, KU-

Leuven

EvaporatorBMBF

SSP infraestructure


MössbauerCollaboration ISOLDE, BMBF,

KU-Leuven, Mössbauer

Collaboration

e-g PACCollaboration ISOLDE, BMBF,

FCT

SSP infraestructure


Gamma Spectrometry Collaboration ISOLDE, BMBF

PL and offline diffusionCollaboration ISOLDE, BMBF

SSP in the ISOLDE hall


GHM beam lineEmission channeling ONLINE

Collaboration ISOLDE, FCT,

KU-Leuven

GLM beam lineCollaboration ISOLDE,

BMBF

On-line diffusion chamberCourtesy: M. Deicher



Implantation

Diffusion annealing up to

1800 °C

Sample serial sectioning by ion sputtering

Catching the sputtered ions by

a tape system (allow D < 10-

19m2/s)

In situ activity measurement

Remote control

On-line diffusion chamber


People working with diffusion at ISOLDE in 2016


“Potassium self-diffusion in a K-rich single-crystal alkali feldspar”

Fabian Hergemoller4th talk

eMS at ISOLDECourtesy: H. P. Gunnlaugsson



Distingu

ish

ferroma

gnetism

/parama

gnetism

Valence state

Site symmetry/

interstitial/substitutional

Distinguish

ferro/para(magnetism)

Binding properties

(through Debye Waller factor)

eMS: can measure low local

concentrations (~10-4 at.%)

Always two elements that

play role:57FeParent (57Mn, 1.5 min) → daughter (57Fe, 100 ns)

Parent (57Co, 272 d) → daughter (57Fe, 100 ns)119SnParent (119In, 2.1 min) → daughter (119*Sn, 18 ns)

Why Mössbauer at ISOLDE?

At ISOLDE/CERN we can measure

spectrum in few minutes

On-line setup: 57Mn (1.5 min) 119In (2.1 min)


Measurement Conditions


Hot lid:

4 positions

Implant/measure under 30°, measure under 60°

Lamp heating from back RT-800 K

Each measurement ~few to 15 minutes

Cold lid (Moscow lid):

Cold finger with LN pumping

Implant/measure single sample under 30°, measure under 60°

Each measurement ~few to 10 minutes

Rotation lid

Implant/measure under 30°/60°

Rotate sample (usually fast)

Measure 0°-70°

Sample can be mounted on magnets (0.6 T || sample normal)

Heated to ~300°C (electrical) in B < 0.3 T

Quenching


Implantation/measurement at T > RT

Sample quickly removed from vacuum (~15 seconds)

External measurement started (while next sample being implanted)

Quenching: sample dropped in LN and measured during decay

External magnetic field

Laser illumination

....

First tested 2014 with moderate success, applied in 2015 with reduced

success, used in 2016 with huge success

General Observations/methods


Temperature series:

Implantation damage at low T’s

Incorporation on regular lattice sites at high T’s

Defect-probe complexes at intermediate T’s

Angular dependent measurements

”Damage” without angular dependence

”Crystalline sites” with angular dependence (if not cubic material)

57Mn implanted TiO2

Slight, but significant angular

dependence

Not Fe in amorphous zones

Cold Source/absorber eMS


Hg produced from spallation

in a molten Pb target197Hg/197Au (PAC) implanted

into ice

Biomolecules prepared and

sample frozen

Isotopes used (since 2000)


MS

Isot.

Parent Lifetime Recoil Det. Target/ion

source

Yields

(s-1)

57Fe 57Mn (b-) 1.5 min. M:93 eV Res. UCx/RILIS few×108

57Co (EC) 272 d. 0.14 eV Res. ZrO/VADIS ~107

119Sn 119In (b-) 2.1 min. M:22 eV Res. UCx/RILIS ~109

119mSn (IT) 291 d. ~0 eV Res. UCx/RILIS ~109 (?)

119Ag (b-)

→119Cd (b-)

→119In (b-)

2.1 s.

2.2 min.

2.4 min.

M:102 eV Res. UCx/RILIS ~few×107

197Au 197Hg (EC) 64 h. ~0 Ge (LT) Pb ~109

151Eu 151Dy (EC)

→151Tb (EC)

→151Gd (EC)

17.9 min.

17.6 h.

123.9 d.

~0 Ge Ta ~109

MS Collaboration

2015

2014

2011

2016

Perturbed Angular Correlationsby J. Schell & G. Correia


PAC: a method to probe hyperfine interaction in matter

26

Strengths

• Sample’s morphology is very flexible: Solids, liquids, molecules...

• Efficiency is almost independent of temperature

• Its a differential time measurement ranging from ns to µs

Weaknesses

Needs radioactive nuclei with:

• suitable decay cascades, nuclear

moments, half-lives

• “complicated” analyzing software

• interpretation is not direct

Opportunities

• Facilities like ISOLDE provide many “new” PAC probes

• Synchrotron radiation can make available more probe elements

• New DFT and Cluster models offer great progresses on interpretation

• New detection methods offer greater efficiency and handling of data (LaBr3 detectors, digital)

• e-gamma, gamma-gamma and beta-gamma should be exploited TOGETHER providing new data and exciting new physics

Threats

• Access to large scale facilities depends on appropriate funding

• Training and know-how (in applied nuclear physics) is vanishing from educational programs

• Traditional European groups are disappearing where deep knowledge of the method was accompanied by a regular production of good work.

ISOLDE Workshop and Users meeting 2016 by Juliana Schell

Why only conventional PAC ISOTOPES?

27

111mCd t1/2 = 48.54 m11

2

−7

2

+

EC = 100 %

111In t1/2 = 2.80 d9

2

+

171 keVγ15

2

+ 151 keVt1/2 = 85 ns

γ1

1

2

+245 keV

111Cd

γ2

1

2

+

β- = 93(3) %

181Hf t1/2 = 42.39 d1

2

−

482 keVγ2

181Ta

5

2

+ 133 keVγ1t1/2 = 10.8 ns

Q (b) µ (µN) A22 I

111mCd +0.765(15) (*) -0.766(3) 0.1786 5/2+

181Hf (**) +2.35(6) +3.29(3) -0.3185(11) 5/2+

+2.16(37) +0.669(16) -0.392(8) 2+

(*)Haas, H. and Correia J. G., Hyp. Int. 198, 133-137, 2010.(**)Singh, B., Nuclear Data Sheets, 199 & Tuli J.K., Academic Press Inc., 1995.

7

2

+


28

H

Lib-N

Na

b-N

KM

Rb

CsPAC

M

Fr

Be

Mgb-N

Ca

Sr

BaM

Ra

Sr

Y

LaM

Ac

Ti

Zr

HfM

VPAC

Nb

TaPAC

M

Cr

Mo

WM

ZnM

CuPAC

Ag

AuM

NiPAC

M

Pd

PtM

Co

RhPAC

IrPAC

M

FeM

RuM

OsM

MnTc

PACM

ReM

B

Al

Ga

InPAC

Tl

C

Si

GePAC

M

N

P

AsPAC

SbM

Bi

O

S

SePAC

TeM

Po

FPAC

Cl

CdPAC

HgPAC

M

SnPAC

M

PbPAC

BrPAC

IM

At

Ne

Ar

KrPAC

M

XeM

Rn

He

CePr

PACM

TbM

GdM

EuPAC

M

SmM

PmM

NdM

DyM

HoM

ErM

TmM

YbPAC

M

LuM

ThM

PaM

BkCm

AmM

PuM

NpM

UM

Cf EsFm

Md

No Lr

Available at ISOLDE NOT available at ISOLDE

g-g & g-e- PAC

g-g & e--g PAC

only e--g PAC

only g-e- PAC

only g-g PAC

PAC Perturbed Angular Correlations

M Mössbauer Effect

Probe elements


PAC RESULTS: dopant incorporation (Cd)

29

111Cd:MoOx γ-γ (151-243 keV)

PAC from decay of 111mCd

0.00

0.02

0.04

0.06

0.00

0.02

0.04

0.06

0.00

0.02

0.04

0.06

0.00

0.02

0.04

0.06

0 50 100 150 200

0.00

0.02

0.04

0.06

RT

100°C

300°C

200°C

120°C

time (ns)

R(t)

0 100 200 300200

220

240

260

280

300

0 100 200 3000.0

0.2

0.4

0.6

0.8

1.0

0 100 200 3000.01

0.1

1

10

100

1000

0 100 200 3000

20

40

60

80

100

0 (

Mra

d/

s)

(

Mra

d/

s)

measurement temperature (oC)

fract

ion

(%

)

EFG1 shows evidence for Cd occupying regular site

on MoO3.

EFG2 shows strong dumping due to:

- irregular lattices sites (and/or)

- damaged environment (and/or)

- the temperature reversability of the EFG1, EFG2

fractions hint an electronic excitation at the dopant

Cd. (to be continued, e.g., with ... e--g PAC)


„Probing the local structure in Multiferroic SmCrO3”Goncalo Oliveira

“Utilization of PAC of radioisotope trackers and DFT calculations to determine local environment of Hg(II) in dithiocarbamate functionalized particles for magnetic

removal of Hg2+ from water”Joao Nuno

Friday“The Electric Field Gradient: A systematic Density Functional Study for Hg adatoms on Graphene”

Abel FentaFriday

Apparatus for surface Physics at ISOLDE CERN (1991)

Apparatus for Surface Physics and Interfaces at CERN

(2003)

(ASPIC)


Apparatus for Surface Physics and Interfaces at CERN


ASPIC• First test in December 1990: 111mCd on a Cu

(100) surface

• UHV 10-10 mbar

• Two deposition stages

• Surface and interfaces studies

• Deposition of radioative ions (but not only)

• Additional characterization

(chemical/structural)

• Beautiful Physics: PAC, MS, surface EC

• Manteinance and upgrade at KU- Leuven

Fig. source: Radioactive ions for surface experiments

CERN-ISC-91-10

Offline and on-line emission

channelingCourtesy: L. Pereira and U. Wahl


Lattice sites of 27Mg in different pre-doped GaN

(IS453 courtesy)


● Electron emission

channeling patterns show

mix of substitutional +

interstitial 27Mg

● Interstitial Mg fraction highest in p-GaN:Mg

● Lowest in n-GaN:Si

Direct evidence for amphoteric character of

Mg that is coupled to the doping type

● Site change interstitial - substitutional MgGa

Activation energy for migration of interstitial

Mg: EM » 1.3 - 2.0 eV

-2

-1

0

1

2

-1 0 1 2 3

(01-

10)

(11-20)

(11-20

)

(01-

10)

1.42 - 1.50

1.33 - 1.42

1.25 - 1.33

1.16 - 1.25

1.07 - 1.16

0.99 - 1.07

0.90 - 0.99

0.82 - 0.90

-1 0 1 2 3

-2

-1

0

1

2

(11-20

)

(11-20)

(b) best fit

1.42 - 1.50

1.33 - 1.42

1.25 - 1.33

1.16 - 1.25

1.07 - 1.16

0.99 - 1.07

0.90 - 0.99

0.82 - 0.90

-1 0 1 2 3

-2

-1

0

1

2

(01-10)

(01-

10)

(11-

20) (11-20)

(d) 100% Mgi(c) 100% SGa

1.59 - 1.70

1.48 - 1.59

1.37 - 1.48

1.26 - 1.37

1.15 - 1.26

1.04 - 1.15

0.93 - 1.04

0.82 - 0.93

-1 0 1 2 3

-2

-1

0

1

2

(01-10)

(11-20)

(a) experiment

1.34 - 1.43

1.26 - 1.34

1.17 - 1.26

1.08 - 1.17

1.00 - 1.08

0.91 - 1.00

0.82 - 0.91

0.74 - 0.82

0 100 200 300 400 500 600 700 800-5

0

5

10

15

20

25

30

35

Interstitial 27

Mg (t1/2

=9.5 min) in GaN of different doping types

Arrhenius step models:

N=1 EM

=2.0 eV

N=105 E

M=1.3 eV

implantation current [pA]: 0.20 0.27 1.4-3.0

nid-GaN

p-GaN

GaN:Mg

n-GaN:Si

inte

rsti

tial

27M

g [

%]

implantation temperature T [°C]

“Lattice location of 27Mg in GaN: latest results using the emission channeling technique”

Ulrich Wahl3rd talk

„Emission Channeling with Timepix position sensitive dectectors”

David Bosne (poster)“Lattice location of implanted transition metals in 3C-

SiC”Ângelo Costa (Friday)

Extra topic: topological insulators (IS612 courtesy)


Semi-metalic surface states originating from non-

trivial topology of the electronic band structure in

the bulk (insulator)

(spintronics, quantum computation...)

Nature Physics 8, 800 (2012) Nature Materials 13, 178 (2014)Phys. Rev. Lett. 112, 186801 (2014) Nature Communications 3, 982 (2012)

Topological crystalline insulators (IS612 courtesy)


cubic

rhombohedral

Pb, Sn or Ge

Te

PbTe

↓

(Pb,Sn)Te

↓

SnTe

↓

(Ge,Sn)Te

↓

GeTe

topological

crystalline

insulator

(TCI)

ferroelectric

Rashba

semiconductor

(FERS)

Rhombohedral distortion: breaking crystal mirror symmetry

...with hyperfine interactions (IS612 courtesy)


0.0 0.1 0.2 0.3 0.4

-2

-1

0

1

2

3

Vzz [1

02

1 V

/m2]

r [Å]

GeTe

SnTe

PbTe

technique parent t1/2 Q [b]

Pb PAC 204mPb 67 min 0.44

Sn e-MS119In 2.4 min

0.094119mSn 293 d

Ge PAC 73As 80 d 0.70

𝜔𝑄 or ∆𝐸𝑄 ∝ 𝑄 𝑉𝑧𝑧

Δr

density functional theory

calculations

to establish relation between

measured HFI parameters and

structural parameters

EC-SLI (IS580)

Emission Channeling with Short-Lived Isotopes (online)


Successful emission channeling measurements on topological insulators

-1

0

1

2

3

<211>

<111>

<110>

0.94

0.99

1.03

1.08

1.13

1.17-1

0

1

2

3

-2 -1 0 1 2

-2 -1 0 1 2

-2

-1

0

1

2

-1

0

1

2

3

<211>

<111>

<110>

-1

0

1

2

3-3 -2 -1 0 1

-3 -2 -1 0 1-3

-2

-1

0

1

2

0.94

0.99

1.05

1.10

1.16

1.21

56Mn (2.6 h)

• Mn as magnetic

dopant

• magnetic

properties

depend on Mn

lattice site (e.g.

substitutional

versus intersitital)

• EC is used to

determine the

lattice location

123Sn (40 min)

• parent: 123In

• isotope used for first time for

EC

• doping with Sn induces a

rhombohedral distortion;

the topological state

(e.g. topological

insulator, Rashba

semiconductor, or trivial)

depends on the

magnitude of this

distortion

• EC is used to

characterize the

distortionexample spectra:

Mn-doped PbTe, implanted at 100 °C

example spectra:

Sn-doped PbTe, implanted at 200 °C

Nobel Prize in Physics 2016


"for theoretical discoveries of topological phase transitions and topological phases of matter"Source: "The Nobel Prize in Physics 2016". Nobelprize.org. Nobel Media AB 2014. Web. 4 Dec 2016.

<http://www.nobelprize.org/nobel_prizes/physics/laureates/2016/>

Acknowledgements

39

BMBF

Bundesministerium für Bildung und ForschungErforschung kondensierter Materie mit Großgeräten

Ausbau und Unterhalt der Einrichtungen an ISOLDE/CERN

Germany, contracts: 05K13TSA, 05K16PGA

M. Deicher, D. Lupascu, J. Schell

FCT

Fundação para a Ciência e a TecnologiaCaracterização de Materiais com Técnicas Nucleares Radioativas -sinergia e complementaridade aplicadas ao treino edesenvolvimento.

Portugal, Project: CERN-FIS-NUC-0004-2015

J.G. Martins Correia

KU-Leuven

Katholieke Universiteit Leuven

Lino Pereira


Acknowledgements

40

Thank you very much for your attention!... to colleagues and collaborators!

Specially the SSP in-house group!


solid state physics program - cern

Documents