English

Near shot-noise limited time-resolved circular dichroism pump-probe spectrometer

Instrumentation and Detectors 2018-04-04 v2 Biological Physics

Abstract

We describe an optical near shot-noise limited time-resolved circular dichroism (TRCD) pump-probe spectrometer capable of reliably measuring {\mu}deg circular dichroism signal with nanosecond time resolution. Such sensitivity is achieved through a modification of existing TRCD designs and introduction of a new data processing protocol that eliminates approximations that have caused substantial nonlinearities in past measurements and allows the measurement of absorption and CD transients simultaneously with a single pump pulse. The exceptional signal-to-noise ratio of the described setup makes TRCD technique applicable to a large range of non-biological and biological systems. The spectrometer was used to record, for the first time, weak TRCD kinetics associated with triplet state energy transfer in the photosynthetic Fenna-Matthews-Olson antenna pigment-protein complex.

Keywords

Cite

@article{arxiv.1706.07754,
  title  = {Near shot-noise limited time-resolved circular dichroism pump-probe spectrometer},
  author = {Valentyn Stadnytskyi and Gregory S. Orf and Robert E. Blankenship and Sergei Savikhin},
  journal= {arXiv preprint arXiv:1706.07754},
  year   = {2018}
}