《厦门大学学报（自然科学版）》

基于飞秒脉冲激光器的时间分辨超快光谱技术已经广泛应用于研究光与物质相互作用、激发态性质、超快动力学等光物理现象,其中瞬态反射光谱是研究固体表界面电荷动力学的有力工具之一.本文总结了瞬态反射光谱分析3类常见的半导体表界面(直接带隙半导体表界面、间接带隙半导体表界面和存在内建电场的半导体表界面)载流子动力学的方法; 分析了前两类半导体表界面瞬态反射光谱特征信号归属,讨论了利用特征光谱信号表征扩散、表面复合、界面电荷转移等动力学过程的原理; 讨论了高掺杂半导体表界面如果存在内建电场的情况下表面反射光谱特征信号的归属,以及如何利用光诱导瞬态电场对反射光谱调制来追踪界面电荷分离和复合的动力学.

The femtosecond ultrafast spectroscopies are widely exploited to investigate photophysical properties,such as light-matter interaction,excited state,ultrafast dynamics,etc.Among these spectroscopic techniques,the transient reflection is especially powerful one for the studies of the photocarrier dynamics at the surfaces and interfaces.In this review article,three analysis methods of transient reflection spectroscopy are summarized,including the transient reflection at the surfaces of the direct bandgap and indirect bandgap semiconductors as well as the heterojunctions with a built-in electric field.Based on the assignment of the transient reflection spectral features,the extraction of the dynamic information regarding the carrier diffusion,surface recombination and interfacial charge transfer are discussed.This review also discusses transient photoreflectance signals arising from the modulation of the photo-induced transient electric field in the presence of the built-in electric field,which has been demonstrated as an effective probe to monitor the interfacial charge separation and recombination.

引言
1 瞬态反射光谱仪器简介
2 瞬态反射和吸收光谱原理简介
3 直接带隙半导体单晶瞬态反射光谱
4 间接带隙半导体单晶瞬态反射光谱
5 瞬态光调制反射光谱
6 总结和展望

图1 瞬态反射光谱装置示意图<br/>Fig.1 Schematic illustration of a transient reflectance spectroscopy setup

图1 瞬态反射光谱装置示意图
Fig.1 Schematic illustration of a transient reflectance spectroscopy setup

图2 In-Ga-As-P薄膜材料瞬态透射、反射和吸收的动力学[22]<br/>Fig.2 The kinetics of transient transmission, reflection, and absorption of the In-Ga-As-P film[22]

图2 In-Ga-As-P薄膜材料瞬态透射、反射和吸收的动力学[22]
Fig.2 The kinetics of transient transmission, reflection, and absorption of the In-Ga-As-P film[22]

图3 MAPbBr3钙钛矿多晶薄膜晶粒大小对其瞬态吸收光谱中透射和反射成分影响[23]<br/>Fig.3 The effect of the grains size of MAPbBr3 perovskite polycrystalline films on the transient reflection and transmission components of it's transient absorption spectra[23]

图3 MAPbBr3钙钛矿多晶薄膜晶粒大小对其瞬态吸收光谱中透射和反射成分影响[23]
Fig.3 The effect of the grains size of MAPbBr3 perovskite polycrystalline films on the transient reflection and transmission components of it's transient absorption spectra[23]

图4 MAPbBr3钙钛矿单晶光学性质[24]<br/>Fig.4 Optical properties of perovskite single crystal MAPbBr3[24]

图4 MAPbBr3钙钛矿单晶光学性质[24]
Fig.4 Optical properties of perovskite single crystal MAPbBr3[24]

图5 MAPbBr3钙钛矿单晶的瞬态反射光谱[24]<br/>Fig.5 Transient reflection spectrum of perovskite single crystal of MAPbBr3[24]

图5 MAPbBr3钙钛矿单晶的瞬态反射光谱[24]
Fig.5 Transient reflection spectrum of perovskite single crystal of MAPbBr3[24]

图6 MAPbBr3钙钛矿单晶的瞬态反射光谱动力学[24]<br/>Fig.6 Transient reflection spectrum dynamics of perovskite single crystal of MAPbBr3[24]

图6 MAPbBr3钙钛矿单晶的瞬态反射光谱动力学[24]
Fig.6 Transient reflection spectrum dynamics of perovskite single crystal of MAPbBr3[24]

图7 MAPbI3钙钛矿单晶和多晶薄膜的瞬态反射光谱表征[10]<br/>Fig.7 Characterization of perovskite single crystal and polycrystall thin film of MAPbI3 by transient reflectance spectroscopy[10]

图7 MAPbI3钙钛矿单晶和多晶薄膜的瞬态反射光谱表征[10]
Fig.7 Characterization of perovskite single crystal and polycrystall thin film of MAPbI3 by transient reflectance spectroscopy[10]

$图8 硅的复折射率[27]<br/>Fig.8 Spectra of complex refractive index of silicon[27]$

图8 硅的复折射率[27]
Fig.8 Spectra of complex refractive index of silicon[27]

图9 硅以及硅-铂界面的瞬态反射光谱[28]<br/>Fig.9 Transient reflection spectra of Si and Si-Pt interface[28]

图9 硅以及硅-铂界面的瞬态反射光谱[28]
Fig.9 Transient reflection spectra of Si and Si-Pt interface[28]

图10 硅表面电荷动力学[28]<br/>Fig.10 Charge dynamics on silicon surface[28]

图10 硅表面电荷动力学[28]
Fig.10 Charge dynamics on silicon surface[28]

图11 硅-铂界面电荷动力学[28]<br/>Fig.11 Charge dynamics at silicon-platinum interface[28]

图11 硅-铂界面电荷动力学[28]
Fig.11 Charge dynamics at silicon-platinum interface[28]

图12 瞬态光调制反射光谱原理示意图[29]<br/>Fig.12 Schematic diagram of transient light modulation reflection spectrum[29]

图12 瞬态光调制反射光谱原理示意图[29]
Fig.12 Schematic diagram of transient light modulation reflection spectrum[29]

图13 p-GaInP2半导体界面瞬态光调制反射光谱[29]<br/>Fig.13 Transient photoreflectance spectra of P-GaInP2 semiconducton interfaces[29]

图13 p-GaInP2半导体界面瞬态光调制反射光谱[29]
Fig.13 Transient photoreflectance spectra of P-GaInP2 semiconducton interfaces[29]

图14 p-GaInP2/Pt和p-GaInP2/TiO2界面瞬态光调制反射光谱动力学比较[29]<br/>Fig.14 Compurision of kinetics of transient photoreflectance in p-GaInP2/Pt and p-GaInP2/TiO2[29]

图14 p-GaInP2/Pt和p-GaInP2/TiO2界面瞬态光调制反射光谱动力学比较[29]
Fig.14 Compurision of kinetics of transient photoreflectance in p-GaInP2/Pt and p-GaInP2/TiO2[29]

[1] LEWIS N S.Research opportunities to advance solar energy utilization[J].Science,2016,351(6271):1920-1929.
[2] GRÄTZEL M.Photoelectrochemical cells[J].Nature,2001,414(6861):338-344.
[3] AMANO H,AKASAKI I,KOZAWA T,et al.Electron beam effects on blue luminescence of zinc-doped GaN[J].Journal of Luminescence,1988,40/41:121-122.
[4] CHEN C C,MA W H,ZHAO J C.Semiconductor-mediated photodegradation of pollutants under visible-light irradiation[J].Chemical Society Reviews,2010,39(11):4206-4219.
[5] BECK S M,WESSEL J E.Picosecond transient reflectivity of unpinned gallium arsenide(100)surfaces[J].Applied Physics Letters,1987,50(3):149-151.
[6] GHOSH T,AHARON S,SHPATZ A,et al.Reflectivity effects on pump-probe spectra of lead halide perovskites:comparing thin films versus nanocrystals[J].ACS Nano,2018,12(6):5719-5725.
[7] MARCINKEVIC∨IUS S,LIUOLIA V,BILLINGSLEY D,et al.Transient photoreflectance of AlInN/GaN hetero-structures[J].AIP Advances,2012,2(4):042148.
[8] SABBAH A J,RIFFE D M.Measurement of silicon surface recombination velocity using ultrafast pump-probe reflectivity in the near infrared[J].Journal of Applied Physics,2000,88(11):6954-6956.
[9] SABBAH A J,RIFFE D M.Femtosecond pump-probe reflectivity study of silicon carrier dynamics[J].Physical Review B,2002,66(16):165217.
[10] TANAKA T,HARATA A,SAWADA T.Subpicose-cond surface-restricted carrier and thermal dynamics by transient reflectivity measurements[J].Journal of Applied Physics,1997,82(8):4033-4038.
[11] CABANILLAS-GONZALEZ J,VIRGILI T,GAMBE-TTA A,et al.Photoinduced transient stark spectroscopy in organic semiconductors:a method for charge mobility determination in the picosecond regime[J].Physical Review Letters,2006,96(10):106601.
[12] CHO G C,KÜTT W,KURZ H.Subpicosecond time-resolved coherent-phonon oscillations in GaAs[J].Physical Review Letters,1990,65(6):764-766.
[13] ISHIOKA K,KITAJIMA M,MISOCHKO O V,et al.Ultrafast phonon dynamics of epitaxial atomic layers of Bi on Si(111)[J].Physical Review B,2015,91(12):125431.
[14] IWAI S,ONO M,MAEDA A,et al.Ultrafast optical switching to a metallic state by photoinduced Mott tran-sition in a halogen-bridged nickel-chain compound[J].Physical Review Letters,2003,91(5):057401.
[15] MANTE P A,STOUMPOS C C,KANATZIDIS M G,et al.Electron-acoustic phonon coupling in single crystal CH3NH3PbI3 perovskites revealed by coherent acoustic phonons[J].Nature Communications,2017,8:14398.
[16] NAGAI M,SHIMANO R,KUWATA-GONOKAMI M.Electron-hole droplet formation in direct-gap semicon-ductors observed by mid-infrared pump-probe spectro-scopy[J].Physical Review Letters,2001,86(25):5795-5798.
[17] OKAMOTO H,MATSUZAKI H,WAKABAYASHI T,et al.Photoinduced metallic state mediated by spin-charge separation in a one-dimensional organic Mott insulator[J].Physical Review Letters,2007,98(3):037401.
[18] PRABHU S S,VENGURLEKAR A S.Dynamics of the pump-probe reflectivity spectra in GaAs and GaN[J].Journal of Applied Physics,2004,95(12):7803-7812.
[19] SCHOENLEIN R W,LIN W Z,FUJIMOTO J G,et al.Femtosecond studies of nonequilibrium electronic processes in metals[J].Physical Review Letters,1987,58(16):1680-1683.
[20] SUN C K,VALLÉE F,ACIOLI L H,et al.Femtosecond-tunable measurement of electron thermalization in gold[J].Physical Review B,1994,50(20):15337-15348.
[21] 黄昆.固体物理学[M].北京:高等教育出版社,1985:445.
[22] WIESENFELD J M,TAYLOR A J.Picosecond band filling in highly excited In-Ga-As-P films[J].Physical Review B,1986,34(12):8740-8749.
[23] LIU J X,LENG J,WANG S P,et al.Artifacts in transient absorption measurements of perovskite films induced by transient reflection from morphological microstructures[J].The Journal of Physical Chemistry Letters,2019,10(1):97-101.
[24] YANG Y,YAN Y,YANG M J,et al.Low surface recom-bination velocity in solution-grown CH3NH3PbBr3 pero-vskite single crystal[J].Nature Communications,2015,6:7961.
[25] ELLIOTT R J.Intensity of optical absorption by excitons[J].Physical Review,1957,108(6):1384-1389.
[26] YANG Y,YANG M J,MOORE D T,et al.Top and bottom surfaces limit carrier lifetime in lead iodide perovskite films[J].Nature Energy,2017,2(2):16207.
[27] ASPNES D E,STUDNA A A.Dielectric functions and optical parameters of Si,Ge,GaP,GaAs,GaSb,InP,InAs,and InSb from 1.5 to 6.0 eV[J].Physical Review B,1983,27(2):985-1009.
[28] ZHANG C J,FAN Y Y,HUANG X C,et al.Hot-carrier transfer at photocatalytic silicon/platinum interfaces[J].The Journal of Chemical Physics,2020,152(14):144705.
[29] YANG Y,GU J,YOUNG J L,et al.Semiconductor interfacial carrier dynamics via photoinduced electric fields[J].Science,2015,350(6264):1061-1065.
[30] YU P Y,CARDONA M.Fundamentals of semiconductors[M].Berlin Heidelberg:Springer-Verlag,2010:305.

备注

引言

1 瞬态反射光谱仪器简介

2 瞬态反射和吸收光谱原理简介

3 直接带隙半导体单晶瞬态反射光谱

4 间接带隙半导体单晶瞬态反射光谱

5 瞬态光调制反射光谱

6 总结和展望

学报简介