huJiiiii j-
(6 )' 531 -5 3 5 (2 0 0 2 )
UP A
an internaiional journal
P lio to lu m in e s c e n c e a n d th e rm o lu m in e s c e n c e in
c r y s ta llin e p h o s p h o r
a c tiv a te d Z B L A N flu o r id e
S S c n g a r, S J D h o b l c * ', B P C h a n d r a ' an d B C B h a ll'
D cparlnicni o f Physics. G oNcrninenl M odel Science C ollejic.
Piichpedhi, Jabalpur-482 00 1 , (^hhansgaih, India
K am la N ehru C ollege, S akkaidara Square, N a p p iii-4 4 0 004. M aharashlia, India
’ P i R avishankai S hukla U m v e is iiy , R aipui 442 0 1 0 . C hhalisgarh
India
R a diological Physics and A d visibly D ivisio n , tihabha A tom ic Research Centre,
T io n ib a y . M u in h a i 4 0 0 0 85. M a h a ia s h tia , India
R -inail
s)dhoble(f'M cdiriinail com
R c i i n \ i t l 11 M i n t h 2 0 0 2 . u n v p t e d 2 2
V hslrail
2002
The Z B L A N
P i ’*^ crys ta llin e phosphoi prepared by solid stale d ilfusion m elhod has been lep o iled
P r'' Phololumincscence study indicates that
i"i, i« (Uie to 'P, —>
transition o( P r'’ ions The delects created by ionising radiation aie studied by ihermoluinmescence
111.Illiiu lic a le tw o piom inent glow peaks at 120 and V50"C due to two delect ceniies the positions ol which aie lound
jiiil i'l • lo iic e n iia lio ii in Z B L A N D elect accuiiiiilalioii was noted to be siiongly dependent on the level o f y-exposuie
I nil' 1^ suggested
,1 Miiiismi: radiation on lum inescence have been investigated in Z B L A N
K m words
ZBLAN
r v e s N os.
7 8 55 H x , 7 8 6 0 K ii
1.
Pr*" phosphor, phololu niinescence, Iheriiiolu iiiinescence
d e te c to rs o l lo n i/in g ra d ia tio n 1121 o ffe r the p o te n tia l fo r lu n a b le
In t n x lu c tio n
/ l i l \ N glas.s fib e rs are v a lu a b le fo r a tlv a ri'
< c o in m u m e a lio n s ,
iiis'iliLitl and m a n u fa c tu r in g te c h n o lo g ie s u s in g lasers. R a re e a rth
i"n d o p e d Z B L A N
Phololuniinescence and ellecls
the intensity ol emission ai 400
technique riieimoluiimiesceiu'e
to depend on the radiation dose
A suitalile explanation ol these
g la s s h a s s h o w n f a v o u r a b l e p h y s ic a l
p io p u iic s in u p c o n v e r s io n fib e r la s e r [ L 2 | , fib e r a m p lifie r s l.T,4]
Hid ih r c c -d im c n s io n d is p la y [ 5 , 6 ] U p c o n v e r s io n lu m in e s c e n c e
Hid Its m e c h a n is m h a v e b e e n s tu d ie d in Z B L A N g lass d o p e d
rare e a r th io n s [ 7 , 8 1 in o r d e r to in c re a s e u p c o n v e r s io n
icncy o f ra re e a r th io n s , Yb^"*^ io n s arc o fte n used to s e n s itiv e
'Hic earth lu m in e s c e n t c e n tre s [9 , lO ]
la s e r a c tio n at n e a r u llr a v io lc l w a v e le n g th s . R e c e n tly , th ere has
b e en a re n e w e d m lc rc s l in s tu d y in g Pr'^ d o p e d m a te ria ls lo r
la s e r p u rp o s e s , b o th c o n lin u o u s w a v e an d p u ls e d , in c ry s ta ls
su ch as Y A l O , : P r " l 13 | an d L a C I,:P r 'M M | as w e ll as in o p tic a l
lib e rs 1 1 5 | In o rd e r to d e v e lo p Pr^^ e m is s io n in d iffe r e n t lasci
host m a te ria ls , o u r w o r k c o n c e n tra te d on Z B L A N h e a v y m e ta l
H u o rid e m a te ria l. R e c e n t in te rest in the d c v c lo p m c n i o f ih e lo n g liv e d sp ace q u a lifie d o p iic a l d e v ic e s has s p a rk e d Ih e res earc h
o n the e ffe c ts o f h ig h e n e rg y r a d ia tio n u p o n n o n -lin e a r o p tic s
an d la s e r m a te ria ls . W h ile it has b e en w c ll-d o c u m c n lc d th at the
1he ir iv a le n t p r a s e o d y m iu m (Pr^^) to n is an a tira e tiv c o p tic a l
e x p o s u re o f la s e r c ry s ta ls an d la s e r m a te ria ls o l ^ G o y -ra y s
‘“^ iiw u o r, s in c e its e n e r g y le v e l s p e c tr u m c o n ta in s s e v e ra l
in d u c e s d e fe c ts an d c o lo u r c e n tre s 1 16 ]. R o s e an d c o w o rk e rs
“K iastable m u ltip le s 'G ^ , 'D , ,
^ t h a t o f f e r th e p o s s ib ility o l
[I7 -1 9 ]
h a v e s h o w n th at the e x p o s u re o f L iY F ^ : N d and
^'niultancous e m is s io n in th e b lu e , g re e n , o ra n g e , re d an d in fra re d
N d : Y A G la s e r c ry s ta ls to y -ra y s an d h ig h e n e rg y p ro to n s c re ate
111]. F u r t h e r m o r e , th e b r o a d -b a n d in te r c o n fig u r a tio n a l
d e fe c t c e n tre s an d re s u lt in d e c re a s e in th e o p tic a l p e rfo rm a n c e .
4 f5 d tr a n s itio n o f Pr^'' w h ic h a re u s e d in s c in tilla to r
T h e c re a tio n o f th e d e fe c ts le a d s to th e d e g ra d a tio n o f o p tic a l
^
p ro p e rtie s [1 7 ,2 0 ].
^ ‘Ticspondirig A u th o r
0 2 ( K )2 1 A C S
S Seriffan S J Dhohle, B P Chandra and B C Bhatt
532
T h e r a d ia tio n in d u c e d d e fe c ts in P r ’^ a c tiv a te d Z B L A N la s e r
host m a te ria l arc re p o rte d in this p a p er. T o stu d y th e lu m in e s c e n c e
a n d th e e f f e c t o f io n i z in g r a d ia tio n s o n lu m in e s c e n c e , th e
Z B L A N : Pr^^ la s e r m a te r ia l w a s e x p o s e d to y -r a y s , th e d e fe c ts
3.
Results and discussions
F ig u r e 2 s h o w s p h o to lu m in e s c e n c e ( P L ) e m is s io n spectrum lor
Z B L A N : P r ’ ^. A s tro n g e m is s io n is o b s e r v e d a ro u n d 4(X) nm
(tr a n s itio n o f ^P, —> ^H^), e x c ite d a t 2 4 5 n m w a v e le n g th . Besides
c re a te d w e r e s tu d ie d b y m e a n s o f th e m io lu m in e s c e n c e ( T L )
te c h n iq u e .
2.
Experimental
T h e P r'" d o p e d Z B L . A N
la s e r m a te r ia l w a s p re p a re d b y s o lid
state d iffu s io n m e th o d Z B L A N is ilu o r id e c o m b in e d w ith m e ta ls ,
z ir c o n iu m , b a r iu m , la n th a n u m , a lu m in iu m a n d s o d iu m h e n c e
a c r o n y m Z B L A N . F lu o rid e s arc a lw a y s p r e fe r re d hosts fo r Pr^^,
d u e to th e ir lo w p h o n o n e n e r g is e d w h ic h re s u lt m h ig h e r g a in
a n d h ig h q u a n tu m e ffic ie n c y . D if f e r e n t c o n c e n tra tio n s o f P r^'
d o p e d Z B L A N Ilu o r id e p h o s p h o r h a v e b e e n p re p a re d w it h th e
m o le % c o m p o s itio n ( 5 3 - x ) Z r F j- 2 0 B a F , - 4 L a F ^ - 3 A IF ,- 2 0 N a F - x
F^rF, (w h e r e x is th e c o n c e n tr a tio n o f F^r'" its v a lu e s x = 0 . 0 2 to I
m o le % ) A l l a b o v e s ta r tin g m a te r ia ls w e r e th o r o u g h ly m ix e d
W avelength (nm)
an d a n n e a le d at 4 0 0 ”C f o r 4 h o u rs a n d th e n fire d a t K 0 0 ° C fo r 2 4
h o u rs . T h e r e s u ltin g c o m p o u n d w a s s lo w ly c o o le d to r o o m
le m p e ra tu r c , c ru s h e d to fin e p o w d e r, a n n e a le d at 7 5 0 ° C fo r o n e
h o u r an d th e n q u e n c h e d to r o o m te m p e r a tu re . F o r m a tio n o f
c ry s ta llin e Z B L A N w a s c o n fir m e d b y o b ta in in g X - r a y d iffr a c tio n
( X R D ) p a tte rn s h o w n in F ig u r e I .
F ig u r e 2. P hotoluniincscencc em ission spectra ol Z B L A N
m ole %) phosphor (e x c ita tio n w a v e le n g th is 24.S nm )
th is tw o s m a ll p e a k s w e r e o b s e r v e d a r o u n d 4 8 2 nm due lo
tra n s itio n ^Po
'Fl^ o f Pr^" a n d at lo n g e r sid e 7 7 9 n m (traixsiuon
o f 'D ^ —> 'H ^ ). T h e c o rr e s p o n d in g e x c ita tio n s p c c tm m is shown
in F ig u r e 3. T o s tu d y in flu e n c e o f Pr^^ io n o n e m is s io n iniciisih
c o n c e n tra tio n o f Pr^^ (P r F ^ ) w a s v a r ie d fr o m 0 . 0 2 to I m ole ‘ i
F ig u r e 4 s h o w s r e la tiv e re s p o n s e w it h c o n c e n tra tio n o f F \ * ion
fo r lo w e r c o n c e n tra tio n s fr o m 0.02 to 1 0 m o le
the emission
in te n s ity o f 4 0 0 n m p e a k in c re a s e s an d b e c o m e s m a x im u m Im
0 . 0 5 m o l e % o i P r '^ io n . I t s ta r ts d e c r e a s in g fo r hiehei
c o n c e n tra tio n (a b o v e 0 .3 m o le % ) . T h e e m is s io n inlcnsiiies in
a r b itra r y u n its fo r 4 (X ) n m , 4 8 2 a n d 7 7 9 n m p e a k s arc tabulated as
b e lo w in T a b le 1. T h e d e c re a s e in e m is s io n in te n s ity lo r hi^liei
c o n c e n tra tio n s b e y o n d 0 .0 5 m o le % o f P r'" io n in Z B L A N riu)
F ig u r e
1. X -r a y s
d it f r a c iio n
(X R D )
p a lle rn
ot Z B L A N
P r ’^
ph o sp h o r
P h o lo lu m in c s c c n c e o f v a r io u s c o n c e n tra tio n s o f Pr^^ d o p e d
ZBLAN
w a s s t u d ie d o n a H i t a c h i F 4 0 0 0 f lu o r e s c e n c e
s p e c tro p h o to m e te r. T h e s a m e a m o u n t o f s a m p le w a s u sed e v e r y
lim e Fitnission an d e x c ita tio n s p e c tra w e r e re c o rd e d w ith s p ectra l
s lit w id th o f I n m . E x p o s u r e to y -r a y s w a s g iv e n u s in g a '^‘C o
s o u rc e . T h c |;m o lu m in c s c c n c c g lo w c u rv e s w e r e re c o r d e d w it h a
set u p c o n s is tin g o f a s m a ll m e ta l p la te h e a te d d ir e c tly u s in g a
te m p e ra tu re p r o g r a m m e r, p h o to m u ltip lie r ( 9 3 1 B ), d .c . a m p lif ie r
a n d a m i l l i v o l t re c o rd e r. 5 m g o f p h o s p h o r w.as h e a te d e v e r y
tim e at th e ra te o f 5 K /m i n .
W avelength (nm)
F ig u r e 3 . P hotolum inescence e x c ita tio n spectrum o f
m ole % ) phosphor (em ission w av e le n g th is 4(X) nm ).
Z B L A N . Hr'"
Photoluminescence and thermoluminescence etc
he clue to the concentration quenching as Pr’* is a very special
ease lor concentration quenching. Luminescence of rare earth
ions such as Eu^*, Cd *, Ce^* and Tb’* originates from energy
migration of killer sites. The quenchine of the llITTII
533
glow curve of ZBLAN ; IV^ exposed to y-rays for 1 Gy. The
appearance of inten.se TL glow peak at higher temperature 350D
and another peak at low temperature 120“C indicates that two
400nm
400
300482nm ^
20 0 -
100“
779 nm
_LJ.,UXL
0 1
F ig u r e 5 . Th cim o lu m in escen cc glow cu ive o f Z B L A N Pr'^ (0 05 mole
exposed lo 1 Gy o f y rays
1
typ e s o f d e fe c ts are fo rm e d . T h e d e fe c t p o p u la tio n w as c h a n g in g
Concentration Pr^* ion (mole %)
w ith the Pr^^ im p u r ity c o n c e n tra tio n (F ig u r e 6 ). S in c e d e fe c t
KiHiirc 4. R e lative response curve o f 4 0 0 , 482 and 779 nm P L emission
PLdk with co n c e n iraiio ii o f H r’’ ions in Z B L A N P r‘* phosphois
c o n c e n tra tio n w a s m e a s u re d b y the a m p litu d e o f the T L p e a k ,
d e fe c ts p la y a v e ry im p o r la n l ro le in lu m in e s c e n c e
T o stu d y
th is , T L in te n s ity o f irr a d ia te d s a m p le s w e re re c o rd e d In 1 9 9 3 ,
ciCLiirs in ton p a ir s a n d n o t b y m ig r a tio n . F o r o th e r ra re e a rth
P o lin a n a n d P o a lc [ 2 2 | h a v e s tu d ie d th e in flu e n c e o f io n
i-ms, the s itu a tio n is d if f e r e n t . In ca se o f Pr^' io n , in a d d itio n to
irra d ia tio n d a m a g e o f the Pr^^ lu m in e s c e n c e life tim e at 1.5 3 5 p m
jiK i gy m ig r a tio n , c ro s s r e la x a tio n a ls o o c c u rs . T h e P r'^ io n can
in F r d o p e d s ilic a . T h e file tim e is d e c re a s e d b y ir r a d ia tio n and
he a k ille r o f its n e ig h b o u r ’s lu m in e s c e n c e a n d th e s itu a tio n is
c o n tin u e s to d e c re a s e u n til s a tu ra tio n o c c u rs . T h e y e x p la in e d
imiLli m o re c o m p lic a te d b e c a u s e q u e n c h in g m a y a ls o o c c u r in
th e c h a n g e in lile tir n e in te rm s o f n o n r a d ia liv e e n e rg y tra n s fe r
dll is o late d Pr^^ io n d u e to m u llip h o n o n e m is s io n i f a v a ila b le
processes ca u se d b y ir r a d ia tio n in d u c e d d e fe c ts in the s ilic a .
lic q u c n cic s a re h ig h e n o u g h S in c e th e p o s s ib ility o f a ll these
T h e s e res u lts are a n a lo g o u s w ith o u r res u lts on the T I^ t>f y-
pi IK esses s tr o n g ly d e p e n d s u p o n th e n a tu re o l th e la ttic e an d
irra d ia tio n on the T l , in te n s ity o l tw o p e aks o b s e rv e d in Z B L A N
Its (. o n s iitu c n ts , th e lu m in e s c e n c e b e h a v io u r o f Pr^^ c o m p o u n d s
Pr^^ T h e lo llo w in g e x p e r im e n ts w e r e c a rrie d o u t to c h e c k
is c \|)e L ie d to v a r y s tr o n g ly fr o m la ttic e to la ttic e . T h is is w h a t
w h e th e r r a d ia tio n in d u c e d d e fe c ts arc r e a lly in flu e n c in g the
lias been o b s e rv e d a n d m a y be th e c a u se fo r d e c re a s e in e m is s io n
e m is s io n p ro p e rtie s L a rg e n u m b e r o f d e fe c ts w e re p ro d u c e d m
micnsiiy o l 4 0 0 n m p e a k in Z B L A N : l^r^^for h ig h c o n c e n tra tio n s
*1I V
ions [2 1 ]
iu h lr -l : The P L em ission intensities fo r 4 0 0 , 48 2 and 779 nm peaks
'll /H I.A N
P r’* phosphors
^ 'MKCMiraiion o f
I’l ’ ion in
/H I AN ^niolc % )
E m ission in lc n s iiy (a ib iim is )
(E x c itu U o n w a v e le n g th = 245 nin)
4 0 0 nm
4K2 nm
7 7 9 nm
0 02
438 205
1 4 0 31
58 8^
(I O.S
4 6 2 .4 4 8
16 2 71
6 5 .4 8
0 I
4 6 1 .3 7
181 I I
6 2 25
0 15
4 6 0 88
193 9 8
61 68
0 ^
4 5 0 92
2 1 0 67
6 4 .9 5
10
4 3 5 51
247 44
58 61
h>study the radiation effect on the ZBLAN : Pr'^ the sample
irradiated by *^’Co y-rays for different exposures. Delects
created were studied by TL technique. Figure 5 shows the TL
F ig u r e 6 . R elative T L response curve o f 350“C and 12CTC T L glow peak
w ith concentration o f P r’" ions in Z B L A N .P r '* phosphors.
534
S Sen^^ar, S J Dhohle. B P Chandra and B C Bhatt
ZB LA N ■
(0 .0 5 m o le % ) o f sa m p le. H ig h e r tem p eratu re ( 3 5 0 ^ )
1020 n m w ith th e o u tp u t o f 8 4 0 n m p u m p e d Y b d o p e d silica fih
T L p e a k in te n s ity in c re a s e s u p to 0 . 0 5 m o le % o f Pr'"^ io n s th a t
la s e r. U p c o n v e r s io n la s e r a c tio n in Pr^"^ d o p e d Z B L A N m a icrn i
d e c re a s e s a n d f o r I m o le % o f P r'^ io n s g o e s to m in im u m . T h e
is an a ttr a c tiv e ro u te o f c o n v e r tin g in fr a re d la s e r o u tp u t to visible
lo w e r te m p e r a tu re , 1 2 0 " C T L p e a k in te n s ity in c re a s e s u p to 0 ,1
la s e r o u tp u t. T h e r e h a v e b e e n s e v e ra l re p o rts o f upconversion
m o le
p u m p e d la s e r a c tio n in P r'^ d o p e d Z B L A N [2 3 ,2 4 ], In the visibi
c o n c e n tra tio n o f Pr^' a n d th e n d e c re a s e s f o r h ig h e r
c o n c e n tra tio n o f P r'^ io n
7'h c s e c u rv e s s h o w th a t as P r'" io n s
in c re a s e s c o rr e s p o n d in g T L q u e n c h d u e to p a ir fo r m a tio n o r
la s e r o u tp u t, it m a y b e p o s s ib le to c h a n g e d u e to continuous
e x c ita tio n b y h ig h c r /lo w c r w a v e le n g th in th e Z B L A N : P r g |
a g g r e g a tio n o f lu m in e s c e n c e c e n te rs o f P r'" io n s . T h e r e fo r e ,
A t h ig h e r e x p o s u re , d if f e r e n t e n e r g y tra p s a re c re a te d duo lo
h ig h e n e r g y tra p s a re n o t fo r m e d m u c h , as c o m p a r e d to lo w
the c o lo u r c e n te rs fo r m a tio n in th e Z B L A N : P r ^ and w ith lunhci
e n e rg y n a p s (as in d ic a te d b y 1 2 ( r C 'I'L p e a k ) R a d ia tio n d a m a g e
e x c ita tio n , lig h t g e ts s c a tte re d fr o m th e c o lo u r centers, llic r d o K
m a y be re la te d to th e fo r m a tio n o f lu m in e s c e n c e c e n te rs d u e to
the r a d ia tio n re s is ta n c e is o n e o f fa c to rs o b s e rv e d due in \[
act I v a lo r in th e la ttic e .
m e a s u re m e n ts in Z B L A N : Pr^’" m a te r ia l. T h e v is ib le emission
F ig u re 7 s h o w s the v a r ia tio n o l 3 5 0 " C a n d I 2 0 ”C T L g lo w
p e a k s in te n s ity w ith y -e x p o s u rc s H e r e , m a x im u m p e a k in te n s ity
IS ta k e n as a m e a s u re o f lu m in e s c e n c e c e n te r o r r a d ia tio n d e fe c t
lo r m a tio n
M o r e p r e c is e ly , th e a re a u n d e r th e T L c u rv e g iv e s
th e n u m b e r o f d e te c ts f o r m e d ,
F h e T L e m is s io n in t e n s it y
d e p e n d s u p o n th e n u m b e r o f p o p u la te d tra p s (la ttic e d e fe c ts )
an d r e c o m b in a tio n p r o b a b ilit y o f tr a p p in g a n d r e c o m b in a tio n
sites. H e r e , fo r e s tim a tin g th e r e la tiv e c o n c e n tra tio n o f d e fe c ts .
It IS e n o u g h to ta k e T L p e a k in te n s ity as a m e a s u re o f d e fe c ts
o b s e rv e d b y u p c o n v e rs io n s in Z B L A N : P r
glass is compurabK
w ith th e v is ib le e m is s io n at 4(X ), 4 8 2 , 7 7 9 n m o b s erve d by cxciiimT
w ith 2 4 5 n m . T h e e x c ita tio n o f 2 4 5 n m d ir e c tly c o in c id e s w\[\\
8 5 % e m is s io n o f H g v a p o u r. T h is lo w e r w a v e le n g th cxciiaiion
o f (2 4 5 n m ) Z B L A N
. P r ' ’ c r y s t a llin e p h o s p h o r fo r v is ih k
e m i s s i o n , o p e n s th e n e w
c o n c e p t in th e lu m in e s c c iK \
s p e c tro s c o p y fo r d if f e r e n t a p p lic a tio n s .
4.
Conclu.sions
'I’h e s tro n g P L e m is s io n at 4 0 0 n m in Z B L Z N ; Pr^^ ay V ln lln K
c e n tre lo r m a tio n .
m a te r ia l b y e x c ita tio n o f 2 4 5 n m c o in c id e s w ith H g vapour Tln^
is v e r y u s e lu l as a s o u rc e o f la s e r a c litin , la m p m a te ria ls cV 11
p e a k s a t th e h ig h te m p e r a tu r e o f 35(J“C a n d at 12 0 ”C show ituii
th e tw o ty p e s o f d e fe c t c e n te rs a rc fo r m e d , N u m b e r ol d c k \is
fo r m e d in c re a s e s w ith th e y -r a y e x p o s u re an d rn a x im u ii)
o b .served at 5 G y o f y -r a y e x p o s u re . T h e c r e a tio n o f dclccl.s aKi.
s tr o n g ly d e p e n d s u p o n th e P r^ ’ c o n c e n tr a tio n . T h e deli as
re d u c e the e m is s io n in te n s ity . B y a n n e a lin g the irra d ia ic d sanipL
a b o v e r o o m te m p e r a tu r e th e o r ig in a l la ttic e s tru c tu re could m
be t)b s e rv e d . T h e s e re s u lts m a y be a p p lic a b le lo the
s U k 1>
ni
o p tic a l p r o p e r tie s o f Z B L A N : P r " m a te r ia l fo i use in ih U c K ii'
a p p lic a tio n s
R e f e r cce.s
Ml
L F J o hnson and H .1 C u g e n h e im A p p l
l*hy\ Lfii
I ‘> H
(1^J71)
F ifiiir c 7 . Response plow
l u iv l * ol
^SO'T and 120“C peaks ol Z H L A N
w iih y-rays expo,sine
[2 )
(1 ]
F U u d o s uiul F U n q iih a il / (^pf Stn Am B 12 70^) ( I ^‘15)
Y Duresic. M M o n ilic , J Y A llm n and H Poigniini Llanonu hn
27 6 2 6 ( I U 9 I )
F ig u r e 7 d e p ic ts th a t th e 3 5 0 " C T L p e a k in te n s ity in c re a s e d
14J
M K arasck 7 Op/ Commun
s lo w ly in itia lly u p to 0 .5 G y o l y -r a y e x p o s u re a n d d e c re a s e s at
f,S|
FA
14 1 7 6 ( 1 9 9 1 )
D o w n in g . L Hesi^elink. R _ M M a d a r la n e and ( ' P I
h ig h e x p o s u re ( > I G y o f y - ia y e x p o s u re ). T h e in itia l g r o w th o f
Conf Proc Uise/s and Ekctio-Opucs Soaet\ Annual Meeluv; N
th is c u rv e is d u e to th e f i l l i n g o l p r c e x is lin g tra p s . W h e n the.se
(IE E E S ervice C entre, Piscaiaw ay. NJ. U .SA ), ()6 (I9 9 4 i
are sa tu rated (a t m a x im u m in te n s ity ), n e w d e fe c ts arc then fo n n e d
(6J
b y r a d ia tio n d a m a g e a n d th e re s p o n s e d e c re a s e s . R e s u lts a ls o
s h o w th a t th e n u m b e r o f d e fe c ts c r e a te d is s tr o n g ly d e p e n d e n t
o n th e im p u r ity c o n c e n tr a tio n . B u t th e n a tu re o f re s p o n s e c u rv e
is m o r e o r le s s s i m i l a r a n d in d e p e n d e n t o f P r'^ im p u r it y
c o n c e n tr a tio n .
E A D ow nin g, L H csselink, R M M a d a rla n e , J R Klein. D I
and J Rai.son Technical Digest Series of Conference (Laseo .niil
E le c lr o -O p iic s S o c ie ty ) 9 (O p tic a l S o c ie ty ol A mk- n u i
W ashington, D C , U S A ), p89 (1 9 9 6 )
[7J
(KJ
M B B ro w n and W A Shund Ph\s Rev. Lett 12 .167 (1964)
S Tanabc. K S u zu k i, N S oga and T H unada 7. Lunun. 65 .^4
(1 9 9 .5 )
I .a scr a c tio n o f 4 9 1 , 5 2 0 a n d 6 3 5 n m fr o m Pr^^ d o p e d Z B L A N
[9J
g la ss w a s r e p o rte d in th e lite r a tu r e | 2 3 ] f o r p u m p in g at 8 4 0 a n d
1 lOJ
T M iy a k u w a , D L D e x te r Phys. Rev. B 1 7 0 (1 9 7 0 )
R E A u ze l P n n . of the IEEE 61 785 (1 9 7 3 )
Phololumintsccnve and thennoluminescence etc
A A Karainsku Uuer C rv««/,v. 2“ * cdn (B erlin
(IW ))
ii- l
Springcr-Vcrlau)
E G G u m a n s k a y a , M V K o r /h ik . S A S m irn o v a, V B P avlenko and
A A F e d o ro v
Opt. Spet inm .
|1 9 )
OSA Proc. On Advtimed Solid Sliilf Lisen. (c d s) A lbert
A , P in to a n d T s o Y e e F a n ( O p t i c a l S o c i e t y o f A m e iic a
W a s h in g to n , D C ) 1 5 p l 9 9 ( 1 9 9 3 )
M F. K o ch , A W K u n e y a n d W E Ca,se
AppI PIm U ii 56 10H3
(1 9 9 0 )
liM
( I K)
(U S S R ) 7 2 H6 (l<)9 l)
( I ’ l A B Icek m an n . F H e m e , J P M e y n , T D an g er. E H eu m an n and G
H u b er
117)
B J A tn sh e . S P C ra ig an d S T D av ey J
/.ig /m n /v f lei lino 6 2K7
I I9SK )
T S R o se an d R A F ie ld s OSA on Advaiu e
Teih. Dine.si 2. A lu B B - l/1 8 5 (1 9 9 3 )
T S R ose, R A fields an d R L H utchesson
Solid Suite l.u.iei.\ 2 0 71 (1 9 9 4 )
Solid Suite l.um r.i.
OSA Pioi On AiWumed
T S R ose. C L F in c h e r. D C h e n an d R A F ie ld s
OSA Pioi On
Advuiued Solid Suite Luxei;, 13 28S ( 1 9 9 2 )
(20J
J N O g o io d n ik o v , U V T raitov, A A M a slak o v , A Y K ii/n e lso v
a n d V A M a slo v
Tei li Pliw l.eii 19 ,518 (1 9 9 3 )
( 21 )
G B lasse
|2 2 |
A Polim in and J M P o alc
( 2M
R C S inutt, D ( ' H anna, A C lio p p e r , S T D a \c v , S I- C a ile i and
Piof; Solid Stole Ctieni 18 79 (1 9 8 8 )
D S /c b e s ta P l e c i i o n
J C V ial, R B ai.sson, F M a d e o re an d M J P o irie r J P Im 4 0 9 1 3
(1 9 7 9 )
535
1241
I.e ii
J AppI Pli\\ 73 (4 ), 1669 ( 1 9 9 ))
27 1307 (1 9 9 1 )
J Y A llain , M M im eric and II P o ip n an i
(1991)
Hleuion Lett 11 I I 57