Ultrafast Time-Resolved Imaging Gate

Ultrafast Time-Resolved Spectroscopy

Ultrafast Time-Resolved Photoelectric Emission.

The emission times of laser-triggered electrons from a sharp tungsten tip are directly characterized under ultrafast, near-infrared laser excitation at Keldysh parameters of 6.6<γ<19.1. Emission delays up to 10 fs are observed, which are inferred from the energy gain of photoelectrons emitted into a synchronously driven microwave cavity. Few femtosecond timing resolution is achieved in a config...

Time-resolved luminescence spectroscopy by the optical Kerr-gate method applicable to ultrafast relaxation processes

We have developed a femtosecond time-resolved luminescence spectroscopy by the optical Kerr-gate ~OKG! method to investigate ultrafast carrier dynamics and relaxation processes of materials. Solid glasses with a high nonlinear refractive index were used as the Kerr media to obtain a subpicosecond time resolution. When a quartz plate was used as the Kerr medium, the Kerr efficiency and the instr...

Computational time-resolved imaging

Classical photography uses steady-state illumination and light sensing with focusing optics to capture scene reflectivity as images; temporal variations of the light field are not exploited. This thesis explores the use of time-varying optical illumination and time-resolved sensing along with signal modeling and computational reconstruction. Its purpose is to create new imaging modalities, and ...

Mapping the Ultrafast Dynamics of Adenine onto Its Nucleotide and Oligonucleotides by Time-Resolved Photoelectron Imaging.

The intrinsic photophysics of nucleobases and nucleotides following UV absorption presents a key reductionist step toward understanding the complex photodamage mechanisms occurring in DNA. The decay mechanism of adenine in particular has been the focus of intense investigation, as has how these correlate to those of its more biologically relevant nucleotide and oligonucleotides in aqueous solut...