TY - JOUR
T1 - Method for characterizing bulk recombination using photoinduced absorption
AU - Wilson, Nora
AU - Sandén, Simon
AU - Sandberg, Oskar
AU - Österbacka, Ronald
N1 - fys.
PY - 2017
Y1 - 2017
N2 - The influence of reaction order and trap-assisted recombination on continuous-wave photoinduced absorption measurements is clarified through analytical calculations and numerical simulations. The results reveal the characteristic influence of different trap distributions and enable distinguishing between shallow exponential and Gaussian distributions and systems dominated by direct recombination by analyzing the temperature dependence of the in-phase and quadrature signals. The identifying features are the intensity dependence of the in-phase at high intensity, PAI∝IγHI, and the frequency dependence of the quadrature at low frequency, PAQ∝ωγLF. For direct recombination, γHI and γLF are temperature independent, and for an exponential distribution, they depend on the characteristic energy Ech as γHI=1/(1+Ech/kT) and γLF=kT/Ech, while a Gaussian distribution shows γHI and γLF as functions of I and ω, respectively.
AB - The influence of reaction order and trap-assisted recombination on continuous-wave photoinduced absorption measurements is clarified through analytical calculations and numerical simulations. The results reveal the characteristic influence of different trap distributions and enable distinguishing between shallow exponential and Gaussian distributions and systems dominated by direct recombination by analyzing the temperature dependence of the in-phase and quadrature signals. The identifying features are the intensity dependence of the in-phase at high intensity, PAI∝IγHI, and the frequency dependence of the quadrature at low frequency, PAQ∝ωγLF. For direct recombination, γHI and γLF are temperature independent, and for an exponential distribution, they depend on the characteristic energy Ech as γHI=1/(1+Ech/kT) and γLF=kT/Ech, while a Gaussian distribution shows γHI and γLF as functions of I and ω, respectively.
KW - photoinduced absorption
KW - Organic semiconductors
KW - Charge recombination
KW - recombination
KW - trap-assisted recombination
KW - disordered semiconductors
KW - optical measurements
KW - photoinduced absorption
KW - Organic semiconductors
KW - Charge recombination
KW - recombination
KW - trap-assisted recombination
KW - disordered semiconductors
KW - optical measurements
KW - photoinduced absorption
KW - Organic semiconductors
KW - Charge recombination
KW - recombination
KW - trap-assisted recombination
KW - disordered semiconductors
KW - optical measurements
U2 - 10.1063/1.4977505
DO - 10.1063/1.4977505
M3 - Artikel
SN - 0021-8979
VL - 121
SP - –
JO - Journal of Applied Physics
JF - Journal of Applied Physics
IS - 9
ER -