title: A new pulse width reduction technique for pulsed electron paramagnetic resonance spectroscopy.
abstract: We present a new technique for a microwave pulse modulator that generates a short microwave pulse of approximately 1ns for use in an electron paramagnetic resonance (EPR) spectrometer. A quadruple-frequency multiplier that generates a signal of 16-20GHz from an input of 4-5GHz was employed to reduce the rise and fall times of the pulse prepared by a PIN diode switch. We examined the transient response characteristics of a commercial frequency multiplier and found that the device can function as a multiplier for pulsed signal even though it was designed for continuous wave operation. We applied the technique to a Ku band pulsed EPR spectrometer and successfully observed a spin echo signal with a broad excitation bandwidth of approximately 1.6mT using 80 degrees pulses of 1.5ns.
authors.affiliation: Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aobaku, Sendai 980-8577, Japan. yohba@tagen.tohoku.ac.jp
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Ohba
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Nakazawa
authors.forename: Shunji
authors.initials: S
authors.lastname: Kazama
authors.forename: Yukio
authors.initials: Y
authors.lastname: Mizuta
mesh_terms: D004578:Electron Spin Resonance Spectroscopy / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008872:Microwaves; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*