Optimum control pulses for EPR spectroscopy – development and application

The microwave pulse excitation bandwidth is of crucial importance for pulse electron paramagnetic resonance spectroscopy. For commonly used rectangular pulses the excitation bandwidth is limited by the accessible microwave power. Unfortunately, for many interesting applications, the spectral width by far exceeds the achievable excitation bandwidth. Therefore, sensitivity and significance of such pulse experiments are reduced. One possibility to further increase the excitation bandwidth is via sideband generation, achieved by amplitude- and phase modulation of the microwave. Only recently, fast enough arbitrary waveform generators have become available. We implemented such a versatile pulse shaping unit into our EPR spectrometer. First broadband pulse sequences have been developed in tight collaboration with the group of Prof. Steffen Glaser (TU Munich), implemented and tested in our group. Optimum control theory methodology has been used to generate such broadband excitation pulses. Within this priority program we want to develop new pulse sequences for inversion pulses. This will be done in collaboration with Prof. Steffen Glaser (TU Munich). The pulses will be tested, evaluated and optimized on model systems and finally applied to biological questions.
T. F. Prisner

Prof. Dr. Thomas F. Prisner

Institut für Physikalische und Theoretische Chemie, Goethe-Universität Frankfurt Max-von-Laue-Str. 7, 60438 Frankfurt am Main
Tel.: +49 69 798-29406 Email: Prisner@chemie.uni-frankfurt.de
Fax: +49 69 798-29404 Website: Prisner group