Structure and luminescence of 2D dilute magnetic semiconductors:: Cd1-xMnxSe•L0.5 (L = diamines)

被引:26
作者
Lu, J
Wei, S
Yu, WC
Zhang, HB
Qian, YT [1 ]
机构
[1] Univ Sci & Technol China, Struct Res Lab, Anhua 230026, Peoples R China
[2] Univ Sci & Technol China, Dept Chem, Anhua 230026, Peoples R China
关键词
D O I
10.1021/cm048339y
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The two-dimensional (2D) dilute magnetic semiconductors (Cd1-xMnxSeL0.5)-L-. (L = ethylenediamine, or en, and 1,6-hexanediamine, or hda, x = 0-0.8) were synthesized in an autoclave at 120 degrees C. Ab initio structure solution from X-ray powder diffraction reveals the host compound CdSe center dot hda(0.5) (space group, Pbca, a = 6.8852 angstrom, b = 6.7894 angstrom, c = 27.4113 angstrom) is structurally analogous to CdSe center dot en(0.5), except for a subtle difference in alignment of aliphatic diamine ligands-the hda molecule deflects from the c axis and inclines toward the b axis. CdSe center dot L-0.5 shows well-defined UV absorption and emission peaks, which is attributed to a 2D exciton band edge transition due to size confinement effect in the c direction and the only photoemission level is the 2D exciton ground state with a long lifetime (7 mu s) and intrinsic line width (177 meV) at room temperature. When Cd2+ is partly substituted by Mn2+, a strong Mn2+-related luminescence peak at 2.12 eV (584 nm) is obtained at room temperature, which can be assigned to Mn2+ internal transition (T-4(1) -> (6)A(1)); its excitation peak overlaps with the photoemission peak of the 2D exciton ground state which indicates that the Mn2+ emission is driven by the 2D exciton ground-state transition. For x = 0.02, the photoluminescence intensity of Cd1-xMnxSe center dot hda(0.5) reaches maximum and enhances 28 times compared with that of Cd1-xMnxSe center dot en. When x < 0.05, the Mn2+ luminescence is a characteristic single-exponential decay process with a well-defined constant lifetime of 375 mu s. Electron spin resonance spectra show that Mn2+ substitutes Cd2+ ion and forms a [MnSe3N] coordination tetrahedron and that there are isolated Mn2+ luminescence centers in Cd1-xMnxSe center dot hda(0.5) (x < 0.05), which is the key factor for their stronger luminescence character compared to Cd1-xMnxSe center dot en(0.5).
引用
收藏
页码:1698 / 1703
页数:6
相关论文
共 32 条
[1]   RAMAN-SPECTROSCOPY OF 2 NOVEL SEMICONDUCTORS AND RELATED SUPERLATTICES - CUBIC CD1-XMNXSE AND CD1-XZNXSE [J].
ALONSO, RG ;
SUH, EK ;
RAMDAS, AK ;
SAMARTH, N ;
LUO, H ;
FURDYNA, JK .
PHYSICAL REVIEW B, 1989, 40 (06) :3720-3728
[2]  
ALTOMARE A, EXPO PACKAGE FULL PA
[3]   INTERBAND FARADAY-ROTATION IN DILUTED MAGNETIC SEMICONDUCTORS - ZN1-XMNXTE AND CD1-XMNXTE [J].
BARTHOLOMEW, DU ;
FURDYNA, JK ;
RAMDAS, AK .
PHYSICAL REVIEW B, 1986, 34 (10) :6943-6950
[4]   EPR spectra of Mn2+-doped ZnS quantum dots [J].
Beermann, PAG ;
McGarvey, BR ;
Muralidharan, S ;
Sung, RCW .
CHEMISTRY OF MATERIALS, 2004, 16 (05) :915-918
[5]   Effect of Mn2+ concentration in ZnS nanoparticles on photoluminescence and electron-spin-resonance spectra [J].
Borse, PH ;
Srinivas, D ;
Shinde, RF ;
Date, SK ;
Vogel, W ;
Kulkarni, SK .
PHYSICAL REVIEW B, 1999, 60 (12) :8659-8664
[6]   SPECTROSCOPIC IDENTIFICATION OF THE LUMINESCENCE MECHANISM OF HIGHLY POROUS SILICON [J].
CALCOTT, PDJ ;
NASH, KJ ;
CANHAM, LT ;
KANE, MJ ;
BRUMHEAD, D .
JOURNAL OF LUMINESCENCE, 1993, 57 (1-6) :257-269
[7]   Multiple temperature regimes of radiative decay in CdSe nanocrystal quantum dots: Intrinsic limits to the dark-exciton lifetime [J].
Crooker, SA ;
Barrick, T ;
Hollingsworth, JA ;
Klimov, VI .
APPLIED PHYSICS LETTERS, 2003, 82 (17) :2793-2795
[8]   SPIN SUPERLATTICE FORMATION IN ZNSE ZN1-XMNXSE MULTILAYERS [J].
DAI, N ;
LUO, H ;
ZHANG, FC ;
SAMARTH, N ;
DOBROWOLSKA, M ;
FURDYNA, JK .
PHYSICAL REVIEW LETTERS, 1991, 67 (27) :3824-3827
[9]  
Deng YB, 2003, ACTA MATH SCI, V23, P1
[10]   Band-edge exciton in quantum dots of semiconductors with a degenerate valence band: Dark and bright exciton states [J].
Efros, AL ;
Rosen, M ;
Kuno, M ;
Nirmal, M ;
Norris, DJ ;
Bawendi, M .
PHYSICAL REVIEW B, 1996, 54 (07) :4843-4856