Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

Quasi – cw superradiant THz facilitiy TELBE: Opportunities and Challenges

M. Gensch

HZDR

&

THODIAC collaboration

Seite 2 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

Center for high power radiation sources

Seite 3 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

upgraded ELBE accelerator

beam energy:

up to 40 MeV

three modes of operation:

1. up to 70 pC @ 13 MHz (thermionic gun)

2. up to 1 nC @ few Hz to 500 kHz (SRF Gun)

3. diagnostic mode (not more than 100 mA): e.g. 100 pc @ 100 kHz

Seite 4 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

upgraded ELBE accelerator

ps – electron bunches fs – electron bunches

beam energy:

up to 40 MeV

three modes of operation:

1. up to 70 pC @ 13 MHz (thermionic gun)

2. up to 1 nC @ few Hz to 500 kHz (SRF Gun)

3. diagnostic mode (not more than 100 mA): e.g. 100 pc @ 100 kHz

Seite 5 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

Super-radiant THz user facility:

design goals:

• quasi – cw rep rates: few Hz to 13 MHz

(adjustable)

• pulsenergies: up to 100 mJ

• spectral properties: 0.1 – 3 THz

narrow band (10-20%) / broad band

• polarization: linear/radially

• sub 100 fs synchronisation to fs-laser

• intrinsic synchonisation CTR<->undulator

-> commissioning by THODIAC until 2016?

ARD – test facility for e bunch diagnostic on

quasi – cw electron beams:

• quasi – cw reprates: few Hz to 13 MHz

(adjustable)

• e-bunch charge: few pC – 1 nC

• diagnostic table in TELBE lab (access to

undulator & CTR source + fs laser +

FTIR spectrometer)

• monitor test stand in e-beamline directly

after THz sources

-> access via THODIAC collaboration

Opportunities

Seite 6 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

Opportunities: ARD test facility

ps – electron bunches fs – electron bunches

Monitor test stand: TELBE lab:

Seite 7 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

Opportunities: ARD test facility

BCM (coll. DESY-FLA)

BCM & BAM

Monitor

test stand

neu

tron

so

urc

e (n

-EL

BE

) &

laser-e

lectro

n in

tera

ctio

n e

xp

.

positron

source

(p-ELBE).

BCM & BAM (coll. DESY – FLA, DESY-MSK, DESY-MDI)

(coll. DESY – FSFL, DESY-FLA)

Seite 8 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

Opportunities: TELBE

incoherent

coherent (super-radiant)

hot topic in ultra fast science are THz field driven processes

super-radiant THz sources provide the highest THz peak fields

available to date!

0 1 2 3 4 5

Inte

nsity /

a.u

.

Time/ ps

0 1 2 3 4 5

ET

Hz /

MV

/cm

Time/ ps

3 THz ~ 100 mm ~ 300 fs

Seite 9 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

incoherent

coherent

(super-radiant)

hot topic in ultra fast science are THz field driven processes

super-radiant THz sources provide the highest THz peak fields

available to date!

development of peak-field since 2001

Opportunities: TELBE

Seite 10 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

incoherent

coherent

(super-radiant)

hot topic in ultra-fast science have recently become THz field driven processes

super-radiant THz sources provide the highest THz peak fields available to date!

up to now record fields at high electron energy linacs

development of peak-field since 2001

Opportunities: TELBE

120 MeV

700 MeV

20-23 GeV

40 MeV

Seite 11 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

FLASH 2007 Hamburg

TELBE 2012 Dresden

Jlab 2001 Newport News USA

FEL technology

1970´s

fundamental question:

Is a super-radiant THz user facility based on a low energy electron

accelerator feasible?

FLUTE 2013 Karslruhe

1 10 100 1k 10k 100k 1M 10M100M 1G1E-4

1E-3

0,01

0,1

1

10

100

1000

BESSY VSR* &

ANKA C* upgrade

FLASH

FLUTE*

FELBE

TELBE*

(0.1 - 3 THz)

laser-driven

table top THz

sources

pu

lse

en

erg

y /

mJ

pulses / s

low alpha

storage rings

*design parameters

Challenge: TELBE

plot under discussion!

Seite 12 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

THz photondiagnostic collab. (THODIAC)

N. Stojanovic / DESY

H.W. Hübers / TUB, DLR

A. Fisher / SLAC

A.S. Müller / KIT

G.P. Williams / Jlab

G. Ulm / PTB

M. Gensch / HZDR

S. Kovalev / HZDR

G. Geloni / X-FEL

…..

THODIAC – TELBE team

(nightshift 03/2013)

pilot „friendly“

users/advisors: A. Cavalleri – MPSD

T. Cowan - HZDR

A. Deac – HZDR

J. Heberle – FUB

M. Helm - HZDR

R. Huber – U Regensburg

A. Irmann - HZDR

T. Kampfrath – FHI

S. Kehr/L.M.Eng – TUD

J. Lindner – HZDR

A. Lindenberg - SLAC

A. Malnasi – U Budapest

I. Radu – HZB

H. Schneider - HZDR

R. Tobey – U Groningen

S. Wall – ICFO

S. Winnerl - HZDR

S. Zvyagin – HZDR

Seite 13 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

DESY (FLASH) <-> HZDR (TELBE)

THODIAC – TELBE team

(nightshift 03/2013)

joint beamtimes: joint developements/

know how transfer

joint projects

HZDR – FTIR spectrometer @

FLASH (03/2012)

joint experiments @ FELBE

and FLASH

0,1 1 10

20

40

60

80

100

FELBE

FLASH

pu

lse e

nerg

y [µ

J]

frequency [THz]

TELBE

BMBF projects:

1. PIDID (2010 – 2013)

- EOS at ELBE

- optical afterburner at FLASH

2. High repetion rate THz

sources at FLASH II

(2012 – 2015)

- CTR/CDR source

HGF:

ARD – ST3 (diagnostic/synch) BAM

BCM

M1 -

chamber

THz Delay chamber

Seite 14 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

• TELBE

• First results from Commissioning

Seite 15 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

CDR/CTR source

Undulator

TELBE facility

0 1 2 3 4 5

ET

Hz / M

V/c

m

time / ps

3 THz pulse

10% BW

FLASH 2008

0 1 2 3 4 5

ET

Hz / M

V/c

m

Time/ ps

quasi-single cycle pulse

broad band (0.1 - 3 THz)

TELBE lab (table top)

CTR/CDR

Undulator if generated by same electron

bunch:

-> intrinsically synchronized

to one another!

Seite 16 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

TELBE / HZDR

•Spectral range: 3 – 0.1 THz

•Spectral bandwidth: 11% (undulator), 100% (CTR)

•Reprate: 100 kHz/13 MHz

•Pulse energy: 100 mJ/ 1 mJ

•Average power: 10 W

•polarization linear (undulator), radial (CTR)

•Pulse duration: 8*tTHz(undulator), < 1 ps (CDR/CTR)

0,1 1 10

20

40

60

80

100

pu

lse e

nerg

y [µ

J]

frequency [THz]

"ultrafast"

THz gap

intrinsically synchronized!

TELBE facility

Seite 17 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

TELBE facility: timeline (status 08/2012)

until 2016 only comissioning

but if possible:

Pilotexperiments with

“friendly” users

in the meantime TELBE serves as HGF test facility for diagnostic on

quasi-cw electron beams

Seite 18 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

• TELBE

• First results (commissioning)

Seite 19 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

Bruker FTIR

Balanced

Detection

Crossed

Polarization

THz

Beamsplitter

ZnTe Beam

Splitter GT Prism ¼

Wave

Wollaston

prism

Babinet

compensator

THz

@ sub 100 pC

100 kHz

PD

Balance

d

Detector GT Prism

Wire grid polarizer

135 30

550

170

Wire grid polarizer

430

50

380

1365mm

to FTIR

70

90

15 50 10

70 40 90

130

25 55

190

1265mm

to EOS

800 nm

78 MHz

100 fs

+various pulse energy meters/detectors/cameras

THz photon diagnostic for first MD shifts

time-domain

frequency

-domain

Seite 20 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

10 15 20 25 30 35 40 45 500

2

4

6

8

10

12

1428. 03. 2013

64 scans

1 cm-1 resolution

inte

nsity / a

.u.

Wavenumber / cm-1

water absorption lines

@ 18.5, 25, 33, 37, 39, 41 cm-1

(possibly also at 14.4 cm-1)

?

0 2 4 6 8 10

No

rm. E

OS

Sig

na

l / a.u

.

time / ps

40pC

5:48AM

10 15 20 25 30 35 40 45 50

Inte

nsity / n

orm

aliz

ed

Wavenumber / cm-1

17 cm-1

22 cm-1

30 cm-1

stabilized: 32 cm-1

0 10 20 30 40

~ 14 ps

corr. ~20 cm-1

EO

S S

ign

al /

a.u

.Time / ps

~ 8 ps

corr. ~ 30 cm-1

CDR/CTR source

THz undulator

beam profile

Frequency-

domain

Time-domain

Pulse energy: few nJ to few 10 nJ

Results of first few MD shifts

Seite 21 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

Summary & Outlook

0,1 1 100,000

0,002

0,004

10

20

30

40

50

60

70

80

90

100

110

pu

lse e

nerg

y [µ

J]

frequency [THz]

"ultrafast"

THz gap

“a long and winding road”

• low pulse energies

• bunch duration still long

(sub ps?)

• spectral bw of undulator

not yet understood

• jitter and drift on few ps timescale

• low energy electrons <-> high THz fields?

but:

• coherent radiation clearly observed

• real time FTIR + EOS available

in control room

• single shot EOS (at 40 Hz reprate)

under development

problems:

• calibrated power measurements between 0.1 – 1 THz?

• operate with new SRF Gun

• electron beam dynamics (optimize bunch compression) Next THODIAC comissioning shifts -> october/november 2013!

TELBE

06/2013

TELBE

design

parameters

Seite 22 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

Acknowledgement

for fruitful discussions: M.C. Hofmann (CFEL/SLAC), M. Vrakking (MBI),

A. Cavalleri, A.L. Cavalieri, M. Foerst (MPSD-CFEL), J. Heberle (FUB),

E. Weckert (DESY), M. Helm, T. Cowan, U. Schramm, P. Michel (HZDR),

R. Mosshammer (MPI), G.W. Williams (Jlab), G.L. Carr (BNL),

G. Wüstefeld, I. Radu, J. Knobloch (HZB), J. Ulrich, G. Ulm (PTB), S

. Wall, T. Kampfrath (FHI), A.S. Fisher (SLAC) , A. Malnasi (Budapest),

TH. Rasing, Kimel (U Niemwegen), R.I. Tobey (U Groningen)

N. Stojanovic, T. Golz, A. Al-Shemmary (DESY), F. Tavella(HIJ), G.A. Geloni (XFEL),

B. Faatz, T. Laarmann, J. Schneider, A. Al-Shemmary, J. Feldhaus, S. Bajt,

H. Wabnitz, L. Bittner, M. Röhling, U. Hahn, M. Hesse, B. Schmidt,

Stephan Wesch, H. Schlarb, B. Steffen, E. Saldin, M.V. Yurkov,

E. Schneidmiller, S. Vilicins. H. Schlarb (DESY), U. Frühling, M. Wieland,

M. Krikunova, M. Drescher, O. Grimm, J. Roßberg (UHH),, H.W. Hübers,

A. Semenov (DLR), W. Seidel, J. Voigtlaender, B. Wustmann (HZDR)

C. Bauer, S. Winnerl, H. Schneider. B. Green, S. Kovalev, U. Lehnert, Jochen Teichert, Rico Schurig, M. Kuntzsch, M Justus, J. Hauser,

+ FWF & FWK+ FWI

Seite 23 Mitglied der Helmholtz-Gemeinschaft Michael Gensch m.gensch@hzdr.de www.hzdr.de HZDR

Acknowledgement

for fruitful discussions: M.C. Hofmann (CFEL/SLAC), M. Vrakking (MBI),

A. Cavalleri, A.L. Cavalieri, M. Foerst (MPSD-CFEL), J. Heberle (FUB),

E. Weckert (DESY), M. Helm, T. Cowan, U. Schramm, P. Michel (HZDR),

R. Mosshammer (MPI), G.W. Williams (Jlab), G.L. Carr (BNL),

G. Wüstefeld, I. Radu, J. Knobloch (HZB), J. Ulrich, G. Ulm (PTB), S

. Wall, T. Kampfrath (FHI), A.S. Fisher (SLAC) , A. Malnasi (Budapest),

TH. Rasing, Kimel (U Niemwegen), R.I. Tobey (U Groningen)

Thank you for

your attention

N. Stojanovic, T. Golz, A. Al-Shemmary (DESY), F. Tavella(HIJ), G.A. Geloni (XFEL),

B. Faatz, T. Laarmann, J. Schneider, A. Al-Shemmary, J. Feldhaus, S. Bajt,

H. Wabnitz, L. Bittner, M. Röhling, U. Hahn, M. Hesse, B. Schmidt,

Stephan Wesch, H. Schlarb, B. Steffen, E. Saldin, M.V. Yurkov,

E. Schneidmiller, S. Vilicins. H. Schlarb (DESY), U. Frühling, M. Wieland,

M. Krikunova, M. Drescher, O. Grimm, J. Roßberg (UHH),, H.W. Hübers,

A. Semenov (DLR), W. Seidel, J. Voigtlaender, B. Wustmann (HZDR)

C. Bauer, S. Winnerl, H. Schneider. B. Green, S. Kovalev, U. Lehnert, Jochen Teichert, Rico Schurig, M. Kuntzsch, M Justus, J. Hauser,

+ FWF & FWK+ FWI

THODIAC – TELBE team

(nightshift 03/2013)