強相関電子系ペロブスカイト遷移金属酸化物による光エレクトロニクス 平成 12 年 11 月 ~ 平成 18 年 3 月 研究代表者 : 花村榮一 ( 千歳科学技術大学光科学部 教授 )

強相関電子系ペロブスカイト遷移金属酸化物による光エレクトロニクス 平成 12 年 11 月 ~ 平成 18 年 3 月 研究代表者 : 花村榮一 ( 千歳科学技術大学光科学部 教授 )

χ αβγω χ αβγωβγ αχ χ -1 -

ω ω Γ ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω -2 -

-3 -

BO 2 (Rutile) TiO 2 YMnO ABO 3, KNbO 3, KTaO AB 3 2 O 4 (Spinel) 3 B 2 O 3 (Corundum) α-fe 2 O 3, Cr 2 O 3,Al 2 O 3 σ -4 -

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χ αβγω χ αβγω α ω ω ω π Γ Γ ω ω ω ω ω ω ω ω ω ω ω ω -6 -

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α γ γ Γ α-fe 2 O 3 α-fe 2 O 3-8 -

ωβγ α α ω χ αβγ ω YMnO 3 YMnO 3 Mn 3+ -9 -

a ( 2ω ) ε χ ( 2ω) ( ω) ( ω) P = E E 0 αβγ γ γ χ ω χ ω () i 1 εχ 0 ( 2ω) P zyy z E 2hω 1 ( c) 1 γ εχ 0 ( 2ω) S yyy z Pz + E 2 2hω E 1 2hω γ χ χ ω χ ωχ ω YMnO 3 (a) χ (i) zyyxy2 (b) χ (c) yyy6 T < T N S x 2 aχ (i) zyy(2ω) Pz bχ (c) yyy(2ω) P z S x cχ (i) zyy(2ω)χ (c) yyy(2ω) S x - 10 -

Σ Σ ( ) z 2 2 Σ{ ξξ ( ) iξ ηη iη ξ ξ ξ } H = J S S + d S S 2 ij i j ij i j ij ij H = D S + D S + D S S + S S anis z i iz iz i i Eanis = V0 Pz ( SxSz + SzSx ) Γ α ω ω ω ω ω ω ω ω ω FEL DB AFM DW operates σ h operates σ v P z, S x, S z -P z, -S x, S z P z, S x, S z P z, -S x, -S z At FEL DB, both (P z, S x ) change sign simultaneously. The clamping of (P z, S x ) at FEL DB is stabilized by E anis. Only S x and S z changes sign. S z is a hidden order-parameter. The AFM DW can exist independently of FEL DB. -11 -

KTaO 3 527 cm -1 CARSω 1 - ω 2 = 770 cm -1 TO4 + TO @BZ KTaO 3 CARS BZTO 4 CARS BZ CARSP 2 1 ħω ω ω ω ω ω µ - 12 -

Γ ω ω ω ω ω ω θ z ω ω ω ω ω ω ω θ ω θ ω ω ω ω ω ω KNbO 3 CARS ω 6565cm µ ω 5952cm µ ω613cm ω ω Wave number[cm -1 ] 23000 21000 19000 17000 15000 13000 11000 9000 calculated SHG-phase matching curve ω 1 +ω 2 Calculated-CARS 2ω 2 2ω 1 7000-15 -5 5 15 25 35 Angle[degree] Experimental value KNbO 3 CARS 11 ω 1 = 6565 cm -1 5µJ/Pulse ω 2 = 5952 cm -1 4µJ/Pulse 2ω 1 = 13130 cm -1 2ω 2 = 11904cm -1 ω 1 +ω 2 = 12517cm -1 ω=613 cm -1 A 1 (TO)mode:610cm -1-13 -

ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ω a Octant I b 4 Octant IIc4 Ti:MgAl 2 O 4 ab - 14 -

µ µ Ti:MgAl 2 O 4 280 nm Mn:MgAl 2 O 4 Mn:MgAl 2 O 4 520 nm - 15 -

a Mn:MgGa 2 O 4 b Mn:MgAl 2 O 4 τ τ - 16 -

1 2 1 N α exp = N e α α e 2 N! N 1 2 1 N β exp = N h β β h 2 N! N αβα β ħω µ µ µ µ χ ω χ ω α - 17 -

Γ Γω ω ω ω ω ω ω ω ω ω α α α - 18 -

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d14 d25 d36 d31 d32 d 33. d 24 d µ α. 15. - 21 -

YCrO 3 () SHG () χ α Temperature dependence of SHG intensity measured at 600 nm and under magnetic field during cooling and heating processes. - 22 -

Schematic diagram of experimental set-up for the phase measurement of nonlinear optical coefficient. - 23 -

Fig. 4 Polarization characteristics of the SHG from quartz and YCrO 3 crystals and superposed signals at several wavelengths. Scales of the signals from single plates are reduced. Fig. 5 SHG intensity and phase of nonlinear susceptibility of YCrO 3. Solid curve indicates absorption spectrum; the SHG intensities are expressed by open squares (experimental) and dashed curve (simulated), and phase values are given by solid circles (experimental) and dotted curve (simulated) - 24 -

..... aab baa bbb bcc...... cbc..... abc...... bca...... cab aaa abb acc........ bab.... cca..... aca.... bbc.. caa cbb ccc... χ χ χ χ - 25 -

Fig. 6 (top) Absorption spectrum and SHG spectra of a GaFeO 3 crystal when light incident on ac plane has polarization parallel to a-axis. (bottom) Absorption spectrum and SHG spectra of a GaFeO 3 crystal when light incident on ac plane has polarization parallel to c-axis. α - 26 -

Fig. 7 Photoluminescence spectra for Ce-doped Al 2 O 3 and SiO 2 prepared by sol-gel method - 27 -

Ca (0.1%):YAlO 3-28 -

Ca:YAlO 3 254 nm Conduction band (Y 4d ) 365 nm luminescence 365 nm non-luminescent center luminescent center Valence band (O 2p ) YAlO 3-29 -

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Fig. 1 Ce(1%)-Al 2 O 3 Fig. 2 Ce(1%)-Al 2 O 3 254nm Intensity (A.U.) Wavelength (nm) Fig. 3 Ce(1%)-Al 2 O 3 Fig. 4-33 -

Fig. 5 Ce(1%)-Al 2 O 3 Fig. 6 Ce(1%)-Al 2 O 3 Fig. 7 Ce(1%)-Al 2 O 3 X Fig. 8 Ce(1%)-Al 2 O 3 X α θ α α - 34 -

Fig. 9 Eu(1%)-Al 2 O 3 Fig. 10 Tb(1%)-Al 2 O 3 Fig. 11 Eu(1%)-Al 2 O 3 Fig. 12 Tb(1%)-Al 2 O 3 α - 35 -

Fig. 13 Tb(0.1%)-Sc 2 O 3 Fig. 14 Tb(0.1%)-Sc 2 O 3 254nm - 36 -

Fig. 15 Tb(0.1%)-Sc 2 O 3 Fig. 16 Tb(0.3%)-Sc 2 O 3 Sc-3d Sc-3d Sc-3d Sc-3d 4f 7 5d S.E. 4f 7 5d S.E. 4f 7 5d 4f 7 5d (i) 5 D 4 (ii) 5 D 4 (iii) 5 D 4 (iv) 5 D 4 7 F 5 S.H. 7 F 5 S.H. 7 F 5 7 F 5 O-2p 7 F 6 O-2p 7 F 6 O-2p 7 F 6 O-2p 7 F 6 Fig. 17 Tb-Sc 2 O 3-37 -

Fig. 18 Ca, Sr, BaYAlO 3 254nm 0.6 0.5 EL Intensity (a. u.) 0.4 0.3 0.2 0.1 0 400 450 500 550 600 650 700 Wavelength (nm) Fig. 19 E Fig. 20-38 -

EL Intensity (a. u.) 0.03 0.025 0.02 0.015 0.01 0.002 0.005 0 0 400 450 500 550 600 650 700 600 650 700 750 800 Wavelength (nm) Wavelength (nm) Fig. 21 Fig. 22 EL Intensity (a. u.) 0.014 0.012 0.01 0.008 0.006 0.004-39 -

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Fig. 23Bi-2223 πσ πσ σ σ π π - 41 -

Fig. 24 MgB 2 Fig. 25 Y-123-42 -

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n-s AFI p-s - 44 -

ρ b ( mω cm ) ρ Ω - 45 - :840 Tc: a-lsco a-lsco NCCO

(Ω Ω 900 100mTorr Tc:10.7K a-ncco ρ Ω Ω a-ncolco p-i-n -46-

p-i-nv-i Nb p-ingaas n-ingaas InP /InGaAs p-n/ - 47 -

anb/p-ingaas/nbv-i bnb/n-ingaas/nbv-i a b Nb µ Nb p-in 0.53 Ga 0.47 As µ (100nm 3x10 19 cm -3 ) n-in 0.53 Ga 0.47 As (100nm 5x10 18 cm -3 ) Nb - 48 -

ξ ξ µ Nb/InGaAs p-n/nb Ar + Ar + STO Ar+ - 49 -

Ar + STOPL Ar + Ar + STOPL - 50 -

(a)kyoto Ar + (b)kyoto Ar + n-sto/ybco n-sto/ybco - 51 -

Al 2 O 3 :Ce Al 2 O 3 :Ce PL - 52 -

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α α α - 57 -

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δ - 59 -

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