2023 CAP Congress / Congrès de l'ACP 2023

Optical Saturation Produces Spurious Evidence for Photoinduced Superconductivity in $\text{K}_{3}\text{C}_{60}$

Jun 19, 2023, 5:15 PM

15m

UNB Kinesiology (Rm. 214 (max. 60))

Oral (Non-Student) / Orale (non-étudiant(e)) Condensed Matter and Materials Physics / Physique de la matière condensée et matériaux (DCMMP-DPMCM) (DCMMP) M3-8 Materials Physics | Physique des matériaux (DPMCM)

Speaker

Steve Dodge

Description

We discuss a systematic error in time-resolved optical conductivity measurements that becomes important at high pump intensities. We show that common optical nonlinearities can distort the photoconductivity depth profile, and by extension distort the photoconductivity spectrum. We show evidence that this distortion is present in existing measurements on $\text{K}_{3}\text{C}_{60}$, and describe how it may create the appearance of photoinduced superconductivity where none exists. Similar errors may emerge in other pump-probe spectroscopy measurements, and we discuss how to correct for them.