Single crystals of LaMgAl11O19:Ti (LMA:Ti) have been grown from the melt by the Verneuil (flame fusion) process. As‐grown crystals contain titanium in both 3+ and 4+ oxidation states. Ti4+ ions can be reduced into the 3+ state by annealing at 1200 °C under hydrogen atmosphere. The crystals exhibit a broadband fluorescence extending from ∼600 to 1200 nm and peaking around 775 nm. The fluorescence lifetime is found to be ∼6 μs at 10 K against ∼4 μs at 300 K; it does not depend significantly on the emission wavelength, this indicating that fluorescence originates mainly from one type of Ti3+ active ions. Electron‐spin‐resonance (ESR) investigations reveal that Ti3+ ions are distributed among the three octahedral sites of the magnetoplumbite structure of the host, with a marked predominance for the regular octahedral site (2a), which contains about 90% of the titanium detected by ESR. Crystal field splitting of the t2g level has been estimated for the three sites and it is proposed that Ti3+ in the (12k) site is adjacent to a cationic defect. This new material is of potential interest for near infrared tunable laser application.

1.
P. Hammerling, A. B. Budgor, and A. Pinto, Eds., Proceedings of the Tunable Laser Conference I, La Jolla, CA (Springer, Berlin, 1985), Vol. 47.
2.
A. B. Budgor, L. Esterowitz, and L. G. Deshazer, Eds., Proceedings of the Tunable Laser Conference II, Zigzag, OR (Springer, Berlin, 1986), Vol. 52.
3.
F. Allario and B. A. Conway, in Proceedings of the Tunable Laser Conference I, La Jolla, CA, edited by P. Hammerling, A. B. Budgor, and A. Pinto (Springer, Berlin, 1985), Vol. 47, p. 42.
4.
F. P. Roullard, in Proceedings of the Tunable Laser Conference I, La Jolla, CA, edited by P. Hammerling, A. B. Budgor, and A. Pinto (Springer, Berlin, 1985), Vol. 47, p. 53.
5.
L. V. Taylor and R. R. Nelms, in Proceedings of the Tunable Laser Conference II, Zigzag, OR, edited by A. B. Budgor, L. Esterowitz, and L. G. Deshazer (Springer, Berlin, 1986), Vol. 52, p. 338.
6.
C. Loth, J. Prelon, P. H. Flamant, and G. Megié, in Proceedings of the Tunable Laser Conference II, Zigzag, OR, edited by A. B. Budgor, L. Esterowitz, and L. G. Deshazer (Springer, Berlin, 1986), Vol. 52, p. 354.
7.
J. C.
Walling
,
O. E.
Peterson
,
H. P.
Jenssen
,
R. C.
Morris
, and
E. W.
O’Dell
,
IEEE J. Quantum Electron.
QE‐16
,
1302
(
1980
).
Google Scholar
 
8.
P. F.
Moulton
,
J. Opt. Soc. Am. B
3
,
125
(
1986
) and references therein.
Google Scholar
Crossref
Search ADS
 
9.
S. K.
Mohapatra
 and
F. A.
Kroger
,
J. Am. Ceram. Soc.
60
,
381
(
1977
).
Google Scholar
Crossref
Search ADS
 
10.
N. A.
Moskvin
,
V. A.
Sandulenko
, and
E. A.
Sidorova
,
J. Appl. Spectrosc. (USSR)
32
,
592
(
1979
).
Google Scholar
Crossref
Search ADS
 
11.
R. C.
Powell
,
J. L.
Caslavsky
,
Z.
Alsmaieb
, and
J. M.
Bowen
,
J. Appl. Phys.
58
,
2331
(
1985
).
Google Scholar
Crossref
Search ADS
 
12.
L. D.
Schearer
,
M.
Leduc
,
D.
Vivien
,
A. M.
Lejus
, and
J.
Théry
,
IEEE J. Quantum Electron.
QE‐22
,
713
(
1986
).
Google Scholar
 
13.
V. M.
Garmash
,
A. A.
Kaminskii
,
M. I.
Polyakov
,
S. E.
Sarkisov
, and
A. A.
Filimonov
,
Phys. Status Solidi A
75
,
Kl11
(
1983
).
Google Scholar
Crossref
Search ADS
 
14.
K. S.
Bagdasarov
,
L. M.
Dorozhkin
,
L. A.
Ermakova
,
A. M.
Kevorkov
,
Y. I.
Krasilov
,
N. T.
Kuznetzov
,
I. I.
Kuratev
,
A. V.
Potemkin
,
L. N.
Raiskaya
,
P. A.
Tseitlin
, and
A. V.
Shestakov
,
Sov. J. Quantum Electron.
13
,
1082
(
1983
).
Google Scholar
Crossref
Search ADS
 
15.
D.
Vivien
,
A. M.
Lejus
,
J.
Théry
,
R.
Collongues
,
J. J.
Aubert
,
R.
Moncorge
, and
F.
Auzel
,
C. R. Acad. Sci. Paris
298
, Ser.
II
,
195
(
1984
).
Google Scholar
 
16.
M.
Gasperin
,
M. C.
Saine
,
A.
Kahn
,
F.
Laville
, and
A. M.
Lejus
,
J. Solid State Chem.
54
,
61
(
1984
).
Google Scholar
Crossref
Search ADS
 
17.
D.
Gourier
,
F.
Laville
,
D.
Vivien
, and
G.
Valladas
,
J. Solid State Chem.
61
,
67
(
1986
).
Google Scholar
Crossref
Search ADS
 
18.
C. Wion and J. J. Aubert (private communication).
19.
B.
Viana
,
A. M.
Lejus
,
D.
Vivien
,
V.
Poncon
, and
G.
Boulon
,
J. Solid State Chem.
71
,
77
(
1987
).
Google Scholar
Crossref
Search ADS
 
20.
K. L. Schepler, in Proceedings of the Tunable Laser Conference II, Zigzag, OR, edited by A. B. Budgor, L. Esterowitz, and L. G. Deshazer (Springer, Berlin, 1986), Vol. 52, p. 235.
21.
N. E.
Kask
,
L. S.
Kornienko
,
T. S.
Mandel’shtam
, and
A. M.
Prokhorov
,
Sov. Phys. Solid State
5
,
1677
(
1964
).
Google Scholar
 
22.
A. Abragam and B. Bleaney, in Electron Paramagnetic Resonance of Transition Metal Ions (Clarendon, Oxford, 1971).
23.
B. R.
McGarvey
,
J. Chem. Phys.
38
,
388
(
1961
).
Google Scholar
Crossref
Search ADS
 
24.
J. P.
Barret
,
D.
Courier
, and
D.
Vivien
,
Solid State Ionics
15
,
127
(
1985
).
Google Scholar
Crossref
Search ADS
 
25.
J. J.
Davies
 and
J. E.
Wertz
,
J. Phys. Chem. Solids
31
,
2489
(
1970
).
Google Scholar
Crossref
Search ADS
 
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