INSTRUMENTATION

Femtosecond Transient Absorption System

This is a home-built system that utilizes an amplified femtosecond laser system (Spectra Physics – Spitfire Ace). The system has an instrument response time of ~0.3 ps, and a delay line capable of measuring up to 2ns. Standard excitation wavelengths: 400nm, 800 nm, 500-780 nm; other wavelengths are optional, pending consultation with the laboratory staff. Detection wavelengths by continuum white light generation using Sapphire or Calcium Fluoride: 400 nm – 950 nm with a gap at 800nm. The system is flexible and can accept many types of samples and sample holders. Magnetic stirring is available. Temperature-controlled experiments between 5oC and 100oC are possible.

Bridge Transient Absorption System

This EOS bridge system (Ultrafast Systems) utilizes the same femtosecond excitation source, and allows measurements up to 400 microseconds. Detection wavelengths: 350-900 nm. Instrument response time is 100 ps.

Nanosecond Flash Photolysis System

The LPS920 Laser Flash Photolysis Transient Absorption system has an instrument response time of 10ns FWHM. It can measure up to seconds and as such can probe biological systems as well. The instrument is capable of working in spectral mode as well as in kinetics mode.

Fluorescence Confocal Microscopy System

This unique microscope, built to our requirements by Andor, allows the study of materials, tissue cultures and live animals. The Yokogawa laser spinning disk confocal supports 5 laser wavelengths from 405nm to 755nm. The microscope has a motorized stage that enables scanning large areas and stitching images. An autofocus unit allows long acquisition times. Okolab environmental enclosure supports tissue cultures. FRAPPA unit makes it possible to photoactivate regions of interest within the field of view to follow the dynamics in time-lapse imaging. 

Terahertz TDS and OPTP

The ZAP-EO from ZOmega offers the capability of measuring Terahertz spectra (between 0.1THz and 2THz) by measuring the transmittance of a single cycle THz pulse, and Fourier transforming the transient – Time Domain Spectroscopy or TDS. This region covers fingerprint wavelengths (1-70cm-1) of many molecules. Optical Pump Terahertz Probe (OPTP) – allows the measurement of kinetics of optically excited species in the terahertz wavelength region for analyzing lifetime of charge carriers as one example.