In this talk, I will introduce a method of how ultrashort pulse (femtosecond 10-15 second or picosecond 10-12 second) can be used to investigate fast transient phenomena in low-dimensional quantum materials. Using a high-repetition-based amplified laser system (250 kHz Reg. amplifier), we can track the photoinduced carrier dynamics in a time-resolved fashion. Specifically, I will introduce optical-pump/optical-probe and optical-pump/terahertz-probe spectroscopy. Following the introduction, I will show our recent works on the time-resolved investigations of exciton dynamics in two-dimensional materials [1-3] and Dirac fermion dynamics in topological insulators [4,5].

References

[1] Cha, S. et al. Nature ommunications 7, 10768 (2016)
[2] Sim, S. et al. Nature Communications 7, 13569 (2016)
[3] Sim, S. et al. under review (2017)
[4] Sim, S. et al. Physical Review B 91, 235438 (2015)
[5] Sim, S. et al. Nature Communications 6, 8814 (2015)