ELEXSYS E600 and E680

High-Frequency/High-Field EPR and ENDOR at 94 GHz

: W-Band bridge

The ELEXSYS family of EPR spectrometers now includes two W-band systems, the E600 and E680. The former is optimized for CW-EPR experiments at 94 GHz, while the E680 operates in both CW- and FT-mode. These high-class research instruments provide a maximum in performance and flexibility while still being easy to operate.

Main features

Precise microwave power setting over a 60 dB range in W-band
All FT-EPR relevant parameters such as pulse power, width and phase are set and monitored on the intermediate frequency (IF) at X-band
High spectral purity, and sensitivity, are achieved by the combination of a fixed frequency oscillator and a PLL circuit

This setup provides an accurate final operating frequency - a must for all g-factor measurements. Flexibility in the system is assured by the modular architecture, allowing the system to be setup as a CW or a combined FT/CW instrument. System operation can be switched from CW to FT or even from W-Band to X-Band at the push of a button. The variable-temperature W-band TeraFlex probehead operates from 4 K to 300 K.

Samples can be exchanged at any temperature. High precision cavity matching, tuning and sample positioning mechanics facilitate high sample throughput with easy handling. For bridge and resonator tuning a 400-MHz wide tuning display is generated and detected on the IF. All these hardware features are complemented by the Xepr software with its easy-to-learn graphical user interface. Xepr software

6 T EPR SC -New W-band superconducting magnet

The second generation of W-band super conducting magnet features a horizontal field, a main coil with 6 T sweep range, permanent leads and a 2 kG high resolution sweep coil. Both, main and sweep-coil are connected to the newly developed power supply. Easy and safe operation is accomplished by a new software interface which allows switching between the two operation modes just by a mouse click.

: MW-Nutation of Coal Sample at 94 GHz

Advantages of high-frequency EPR

increase in spectral resolution due to the higher magnetic field
increase in detection sensitivity for samples of limited quantity due to higher resonator filling factor
increase in orientation selectivity in the investigation of disordered systems
accessibility of spin systems with larger zero-field splitting due to the larger microwave quantum energy
better separation of the ENDOR spectra of different nuclei
improvement in the ENDOR detectability of low-frequency nuclear spins
simplification of spectra due to the reduction of second-order effects at high fields