Energy efficiency increase of NQR spectrometer transmitter at pulse resonance excitation with noise signals

The specific feature of NQR is expansion of spectral lines which is caused not only by dipole-dipole interaction of nuclei, but also by local field nonuniformity caused by the defects and deformation in crystal matrix. Considerable line expansion, which is typical of crystals, requires in pulsed NQR method the optimization of pulse shape and the reserve of transmitter power output. Parametric computer identification was used to study a dependence of parameters of the energy spectra of the output signal of pulsed NQR spectrometer transmitter on the duration of excitation pulses with sine and noise occupation. The energy efficiency of a linear amplifier was calculated and experimental investigations of its temperature conditions were carried out. The energy-efficient broadband transmitter was proposed that can be used in portable setups for the pursuance of research in the field of pulsed NQR spectroscopy, for instance when studying isotopes with quadrupole moments 14N, 35Cl, 63Cu, 69Ga, 71Ga, 113In, 115In and others. [Display omitted] •To study the crystals by NQR, it is necessary to form high-power excitation pulses.•The solution to the problem of rapid identification NQR is the use of noise signals.•Principle of broadband energy efficient transmitter of portable spectrometer offered.•The proposed transmitter was used for studying GaSe and InSe single-crystal samples.