Surface photovoltage effects onp-GaAs (100) from core-level photoelectron spectroscopy using synchrotron radiation and a laser

Dynamics of photo‐excited carriers on GaAs(100) surface studied by ultrafast time‐resolved photoemission

“…Therefore, the slow SPV decay component is considered to be due to the thermionic recombination process. Thermionic decay of the SPV was well studied by the time-resolved photoemission measurement with the combination of synchrotron radiation and laser [12][13][14][15]. The SPV temporal behaviour on the p-type GaAs has also been discussed in our previous report [5].…”

Surface Carrier Dynamics on Semiconductor Studied with Femtosecond Core-Level Photoelectron Spectroscopy Using Extreme Ultraviolet High-Order Harmonic Source

“…Red and blue curves represent the peak with and without laser irradiation with an energy density of 0.1 mJ/cm electric field formed by the separated electrons and holes [2]. The peak shift toward a higher binding energy indicates that the band bends upwards from the bulk to the surface, which is like n-type GaAs [2,3].…”

“…Therefore, the surface carrier dynamics related to the transient SPV is one of the key factors that affect their response time or their conversion efficiency. Although the surface carrier processes has a fundamental time scale of from femtosecond to picosecond order, the SPV dynamics has mainly been measured on a subnanosecond to microsecond time scale with the core-level photoelectron spectroscopy (PES) using the combination of a pulse laser and a synchrotron radiation source [2,3]. As a result, there is little experimental knowledge about the transient SPV dynamics on the fundamental time scale of the surface carrier.…”

Time-Resolved Photoelectron Spectroscopies Using Synchrotron Radiation: Past, Present, and Future

“…It has been quite challenging to measure time-resolved angleresolved PES spectra and time-resolved PES spectra on surface adsorbates with a sub-monolayer coverage. Timeresolved PES experiments using a pump-probe method has been carried out at several SR facilities at UVSOR, 39,46,47) SAGA 43) light source, BESSY [48][49][50] and SOLEIL.…”

“…Dynamical change during relaxation of the SPV effect has been widely used to examine the performance of the time-resolved photoemission measurement system at synchrotron radiation facilities. 41,[43][44][45][46][48][49][50] Figure 18(a) shows the selected tr-PES spectra of Si 2p core-level of a Si(111)7 Â 7 surface, taken by the pumpprobe method. The pump is a laser pulse of h ¼ 1:55 eV with a repetition rate of 1 kHz and the probes are five SR pulses of h ¼ 252 eV with the pulse interval of 684 ns (SPring-8 D-mode operation).…”