vacuum ultraviolet (vuv) spectroscopy of tpb films
DESCRIPTION
Vacuum UltraViolet (VUV) Spectroscopy of TPB films Temperature Effect on TPB Emission Lineshape. Roberto Francini Department of Physics Università di Roma Tor Vergata. Contacts : [email protected] +39 06 7259 4505. SLIDE 1. TPB Workshop 10/19/2012. - PowerPoint PPT PresentationTRANSCRIPT
Vacuum UltraViolet (VUV) Spectroscopy of TPB films Temperature Effect on TPB Emission Lineshape
Roberto FranciniDepartment of Physics
Università di Roma Tor Vergata
Contacts:[email protected]+39 06 7259 4505
SLIDE 1TPB Workshop 10/19/2012
SLIDE 2
Evaporated TPB Films Layer density (µg/cm2)
Glass substrate
167
350
725
900
1175
1450
1875
VIKUITI substrate
50
74
177
317
476
769
1376
1498
Fraction of TPB in polystyrene(Weight fraction %)
1
10
20
40
Samples obtained by evaporation of TPB on different substrates
Samples obtained by dip-coating of glass substrates in polystyrene
containing TPB
TPB Workshop 10/19/2012
Investigated TPB samples were grown at the Gran Sasso National Laboratory LNGS, INFN L’Aquila, Italy
TPB Workshop 10/19/2012 SLIDE 3
Jablonsky diagram
TPB Workshop 10/19/2012 SLIDE 4
Configurational coordinatesdiagram
Absorption SpectraPhoto Excitation (PE) Spectra
PhotoLuminescence (PL) Spectra
TPB Workshop 10/19/2012 SLIDE 5
Vacuum Monochromator McPherson model 234/302Focal length 0.2 m equipped with a 30 Watts Deuterium
lamp model 632 with MgF2 window,
Spectral range 115 – 380 nm.
Closed-cycle Helium CryostatTemperature range
12 – 300 K
Measured VUV Intensity distribution of Deuterium lamp
TPB Workshop 10/19/2012 SLIDE 6
110 120 130 140 150 160 170 1800
5
10
15
Em
issi
on In
tens
ity (a
rb. u
nits
)
Wavelength (nm)
Deuterium Lamp Spectrum
128 nm
350 400 450 500 550 6000
2
4
6
8
10
Emission
Intens
ity (a
rb. u
nits)
Wavelength (nm)
1% 10% 20% 40%
300 350 400 450 5000
1
2
3
Opt
ical D
ensity
Wavelength (nm)
1%
10%
20%
40%
Emission Spectra Excited at 128 nm
TPB in polystyrene on glass
Absorption Spectra
TPB Workshop 10/19/2012 SLIDE 7
0 10 20 30 402
3
4
5
6
7
8
Integr
ated
Emission
Intens
ity (a
rb. u
nits)
TPB fraction in Polystyrene matrix (mass %)
0 10 20 30 40428
432
436
440
444
Peak
Wav
elen
gth
(nm
)
TPB fraction in Polystyrene matrix (mass %)300 400 500 600
0.0
0.5
1.0
1.5
Wavelength (nm)
Opt
ical
Den
sity
2
4
6
8
10
12
Emission Intensity (arb.units)
TPB Workshop 10/19/2012 SLIDE 8
TPB in PMMA
TPB in polystyrene
J. Huang et al., J. Lumin. 81 (4), 285 (1999)
TPB evaporated on glass
Spettri di EmissioneEccitati a 128 nm
250 500 750 1000 1250 1500 1750 2000422
423
424
425
426
427
428
Peak
Wav
elen
gth
(nm
)
TPB density (g/cm2)
250 500 750 1000 1250 1500 1750 20000.6
0.7
0.8
0.9
1.0
1.1
1.2
Emis
sion
Inte
nsity
(arb
. uni
ts)
TPB density (g/cm2)
350 400 450 500 550 600
0
4
8
12
16
20
Emis
sion
Inte
nsity
(arb
. uni
ts)
Wavelength (nm)
350 g/cm2
725 g/cm2
1175g/cm2
1875g/cm2
TPB evaporato su vetro
Emission Spectra Excited at 128 nm
TPB Workshop 10/19/2012 SLIDE 9
0 250 500 750 1000 1250 1500
0.95
1.00
1.05
1.10
1.15
1.20
1.25
1.30
Peak
Em
issi
on In
tens
ity (a
rb. u
nits
)
TPB density (g/cm2)
350 400 450 500 550 600 650
0.5
1.0
1.5
2.0
Emis
sion
Inte
nsity
(arb
. uni
ts)
Wavelength (nm)
300 K250 K
200 K
150 K
87 K
12 K
Sample A7 - 177 g/cm2 TPB-Vikuiti
0 50 100 150 200 250 3000.0
0.2
0.4
0.6
0.8
1.0
Sample A7 - 177 g/cm2 TPB-Vikuiti
Inte
grat
ed E
mis
sion
Inte
nsity
(arb
. uni
ts)
Temperature (K)
TPB evaporated on VIKUITI
TPB Workshop 10/19/2012 SLIDE 10
Emission Spectra Excited at 128 nm
mm
TPB Workshop 10/19/2012 SLIDE 11
Frank-Condon Integrals
Huang-Rhys Factor
ΔQ is the coordinate displacement between the ground state
and the excited state
T = 12 K
1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4
0.01
0.1
1
0.18 eV
TPB evaporated on VIKUITI (177 g/cm2)
Inte
nsity
(arb
. uni
ts)
Energy (eV)
(0,0)(0,4)
(0,5)
- Vibrational mode energy = 0.18 eV = 1450 cm -1
- Stretching mode vibration of trans-butadiene
S = 2
TPB in polystyrene on glass
Emission Spectra of TPBon VIKUITI and in polystyrene
Excited at 128 nmTemperatura 87 K (LAr)
TPB Workshop 10/19/2012 SLIDE 12
350 400 450 500 550 600 6500
1
2
3
4
T = 12 K
50 K
87 K
150 K
200 K
Em
issi
on In
tens
ity (a
rb. u
nits
)
Wavelength (nm)
300 K
exc = 128 nm
Emission Spectra Excited at 128 nm
350 400 450 500 550 6000
4
8
12
16
TPB on VIKUITI TPB in polystyrene on glass
Nor
mal
ized
PL
(arb
. uni
ts)
Wavelength (nm)
T = 87 K
300 320 340 360 380 400 420 440 4600
1
2
3
PE
(arb
. uni
ts)
Wavelength (nm)
(em
= 422 nm) (
emi= 445 nm)
(emi
= 460 nm)
300 350 400 450 500 550 6000
2
4
6
8
PL
(arb
. uni
ts)
Wavelength (nm)
(exc = 265 nm) (exc = 280 nm) (exc = 295 nm) (exc = 348 nm) (exc = 380 nm) (exc = 400 nm)
Campione TPB evaporato su VM2000 (600 g/cm2)
300 320 340 360 380 400 420 440 4600.0
0.5
1.0
1.5
PE
(arb
. uni
ts)
Wavelength (nm)
(emi
= 422 nm) (
emi= 445 nm)
(emi
= 460 nm)
300 350 400 450 500 550 6000
1
2
3
4
PL
(arb
. uni
ts)
Wavelength (nm)
(exc
= 295 nm) (exc= 348 nm) (exc= 380 nm) (exc= 400 nm)
TPB in polistirene su vetrino
Photoluminescence (PL) and Photoexcitation (PE) in the UV-VIS range
TPB Workshop 10/19/2012 SLIDE 13
TPB in polystyrene on glass – T = 300 K
TPB evaporated on VM2000 – 600 μg/cm2 – T = 300 K
TPB Workshop 10/19/2012 SLIDE 14
Emission Spectra (excited at 128 nm) of TPB evaporated on VIKUITI, TPB in polystyrene on glass and of a VIKUITI blank, compared with the emission spectrum of a Sodium Salicylate film on glass.
300 350 400 450 500 550 600 650
0.0
0.4
0.8
1.2
1.6
2.0
Nor
mal
ized
Em
issi
on In
tens
ity (a
rb. u
nits
)
Wavelength (nm)
Sodium Salicylate TPB/polystyrene on glass TPB on VIKUITI
Blank VIKUITI
T = 300 K