The transient electroluminescence(EL)technique is widely used to evaluate the carrier mobility in the field of organic light emitting diodes.The traditional analog detection strategy using oscilloscopes is generally l...The transient electroluminescence(EL)technique is widely used to evaluate the carrier mobility in the field of organic light emitting diodes.The traditional analog detection strategy using oscilloscopes is generally limited since the background noise causes an underestimation of the mobility value.In this paper,we utilize time-correlated single-photon counting(TCSPC)to probe the transient EL for mobility calculation.The measurements on tris(8-hydroxyquinoline)aluminum(Alq3)show that the electron mobilities obtained using the TCSPC technique are slightly higher than those obtained from the analog method at all the investigated voltages.Moreover,the TCSPC mobilities demonstrate weaker dependence on the root of electrical field compared to the oscilloscope mobilities.These improvements are attributed to the unique principle of TCSPC,which quantifies the EL intensity by counting the number of single-photon pulses,improving its single-photon sensitivity and elimi-nating the negative impacts of electrical noise.These advantages make TCSPC a powerful technique in the characterization of time-resolved electroluminescence.展开更多
基金The authors acknowledge the funding from the National Natural Science Foundation of China(Grant Nos.91833304,61975057,and 21788102)the National Key R&D Program of China(No.2020YFA0714604)+2 种基金the Foundation of Guangdong Province(No.2019B121205002)the Guangdong Province Key Laboratory of Luminescence from Molecular Aggregates(No.2019B030301003)by the Open Project Program of Wuhan National Laboratory for Optoelectronics(No.2019WNLOKF016).
文摘The transient electroluminescence(EL)technique is widely used to evaluate the carrier mobility in the field of organic light emitting diodes.The traditional analog detection strategy using oscilloscopes is generally limited since the background noise causes an underestimation of the mobility value.In this paper,we utilize time-correlated single-photon counting(TCSPC)to probe the transient EL for mobility calculation.The measurements on tris(8-hydroxyquinoline)aluminum(Alq3)show that the electron mobilities obtained using the TCSPC technique are slightly higher than those obtained from the analog method at all the investigated voltages.Moreover,the TCSPC mobilities demonstrate weaker dependence on the root of electrical field compared to the oscilloscope mobilities.These improvements are attributed to the unique principle of TCSPC,which quantifies the EL intensity by counting the number of single-photon pulses,improving its single-photon sensitivity and elimi-nating the negative impacts of electrical noise.These advantages make TCSPC a powerful technique in the characterization of time-resolved electroluminescence.
