C) 13K, gin bd viing cam xuat hien hai vach hep vdi cudng do manh d 456nm va 461nm n i m trdn nen cua dam phat quang mau xanh lam tir
2.Sú phu thuoc vi trf va cuong do cua dam phat quang viing da cam-d od 606nm vao mat do nang luong kich thich
vao mat do nang luong kich thich
Khi thav đi mat do nang lugng kich thich ciia \ach 488nm cua laser Argon tir 4.2 \v/cnr đn 33.70 w.'cnr. vi tri cue dai ciia dam 606nm bi dich chu>'en \-e phfa nang lugng Idn khoans 1 ImeV va do rdng ciia dam tang len khoang 48meV (hinh 4j. Day la dac trung didn hinh ciia tai hg]5 biíC xa donor- acceptor. Klii mat do nang lugng kfch thich nhd cac hat tai dien sinh ra ft. do đ birc xa ga>' nen chu > eu bai nhirng cap
Bdo cao tai Hoi nghi Vdi ly toan quoc lan thu VI, Hd Npi 23 -25/11/2005
donor - acceptor d xa vdi nang lugng nhd. Khi tang mat do nang lugng kfch thich. nhung cap donor- acceptor d xa bat dau bao hoa, nhirng cap donor - acceptor d gan \ di nang lugng Idn dugc tang len [2]. Vi the khi tang mat do nang lugng kfch thfch, vi tri cue dai cua dam donor-acceptor dich chuyen ve phia nang lugng Idn \a cudng do ciia dam ciing tang len. Cudng do cua dam 606nm phu thudc vao mat do nang lugng kich thich theo quy luat Jhq= Jki" vdi n ^ 0.6 (hinh 5).
200 300 400 &00 2.0x10"' 2.0x10"' 1.8x10"* ỊSxIO"* 3.1.4x10"* 11.2x10- I 1.0x10-' "^ 8.0x10"* 6.0x10"* 4.0x10* 2.0x10'*
Hinh 2: Pho microRaman ciia tinh the ZnSe khi kich thich bdng buac song 632.8 nm cua
laser He-Ne a 300K e 6D6 7 r^ 606 48 '' ạ J =4,2w/cm* c J^=21 Ow/cm' d: J^=25.3w/cm' e J =33,7w/cm' 600 620 Wavelength ( n i r ; 680
Hinh 3: Pho phdt quang cua tinh the ZnSe vai cdc mat do ndng luang kich thich khdc nhau khi kich thich bdng buac
song 488nm cua laser Argon a 300K
2.0 2.5 3.0 3.5
Energy density (w/cm')
Hinh 4:Suphii thuoc vi tri cue dai dam 606 nm cua tinh th^ ZnSe vdo mat do ndng hcong
kich thich a 300K
1.5 2.0 2.5
Hinh 5: Su phu thuoc cuang do đm 606nm cua tinh the ZnSe vdo mat do
ndn^ hrcmo- kich thich a 300K
Vai nhijna dac diSm tren. chung toi xem rSng dam phat quang a \ img da cam-do
voi cue dai a eóenm la do tai hgp biic xa cua nhung cap donor nong \a acceptor sau a
dn nhaụ'trong do donor nong co ihl la Al [4] ^•a acceptor sau la cac nut khu>et cua
Zn lien kStvoi^Cl (Vzn-Cl)[6].
Bdo cao tai Hoi nghi Vdi ly toan quoc lan thu VI, Hd Npi 23 -25/11/2005
IV. KET LUAN
Ddi vdi tinh thd ZnSe, khi kich thich bing cac budc sdng 365nm va 450nm cua den Xenon thi trong phd phat quang cua nd xuat hien eac vach va cae dam d \iing xanli lam tir 450nm den 500nm va xanh la cay d 570nm. Khi kich thich bang budc sdng 488nm cua laser Argon vdi mat do nang lugng tir 4.2 w/cm' den 33.7 w/cm~ thi trong
phd phat quang ciia no xuit hỉn dam 606nm d viing da cam-đ . Do do cd iY\k diing
tinh the ZnSe de che tao cac didt phat quang trong cac vimg phd naỵ
TAI LIEU THAM KHAO
1. Bô5omeHKỌB.3,BaBU7ioB.B.C.OTn, 21(1987) 191-193 2. B.C.BaBu^oB By 3oaH M-ben, 26 (1984) 1457-1462 2. B.C.BaBu^oB By 3oaH M-ben, 26 (1984) 1457-1462
3. B.H.raBpH.ieHKO, ẠM.FpexoB.OnTMHecKHe CBoi^CTsa ^ọ^y^poBo;lHHKOB,(I987) 429-439 429-439
4. C.B.ranoHCHKO, B.n. rpuOKOBCKMH. 4oK7ia4bi AKaAeMiifi m\^ BCCP. 28n984)
318-320
5. r.H.MBaHOBạ fl-fl.HegeorọiọOTn,]4(1980) 31-35 6. Keizo Morimoto J.Appl physis, 64(1988) 4951-4955 6. Keizo Morimoto J.Appl physis, 64(1988) 4951-4955 (adsbygoogle = window.adsbygoogle || []).push({});
7. K.M.LeẹLe Si Dang and G.D.Watkins, Solid State Communication,35( 1980) 527- 530 8. Yong-Sik lim, Seok - Chan Yoon, AppHed physics letters, 82(2003) 2446-2448 8. Yong-Sik lim, Seok - Chan Yoon, AppHed physics letters, 82(2003) 2446-2448 9. ỌV.Vakulenko, V.M.Kravchenko, Functional Materials, 11 (2004) 90-94
Abstract : Using the wa\'elength of 365nm and 450nm of Xenon lamp to excite ZnSe cr\'stal at temperature about 13K, the luminescence spectra shoNsed light blue band from 450nm to 500nm and green band having maximum peak at 570nm. These bands and lines charactered for radiati\'e recombination of ecxiton bond Zn vacanc\- (V^n) with the contribution of LO phonon, shallow donor-acceptor pairs and impuritỵ The intensity of these bands and lines increased with decreasing temperaturẹ At 300K. \\Tien the ZnSe crystal was excited b}- 488nm of Ar laser with the energy densit}" from 4.2w/cm"^ to 33.7w'cm^luminescence spectra showed an wide orange-red band ha\ing maximum peak shifted to\Nard high energy (up to 11 meV). These bands charactered for radiative recombination of near neighbour shallow donor- deep acceptor pairs.
DAI HOC QUOC GIA HA NQI
KHOA Sir PHAM
BUI HONG VAN