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Impact of shock waves on non-linear optical materials bring about a lot of unknown behaviors of materials and such kinds of shock wave recovery experiments are highly required for the better understanding of material-property relationship. In the present context, we have performed experiments on the impact of structural properties of ammonium dihydrogen phosphate (ADP) samples under shock wave loaded conditions and the results of the test samples have been evaluated by X-ray diffraction (XRD), Raman spectroscopy, diffused reflectance spectroscopy (DRS) and field emission scanning electron microscopic (FESEM) technique. Interestingly, prismatic face of ADP shows loss of degree of crystallinity whereas pyramidal face shows enhancement of crystalline nature with respect to number of shock pulses due to shock wave induced dynamic re-crystallization. Hence, the present problem is worthy enough to unearth and understand the anisotropic nature of the ADP crystal and their structural modifications at shock wave loaded conditions.

Based on the importance of the shock recovery experiments, the authors report the structural and optical properties of pure and 0.001 M dye-doped potassium dihydrogen phosphate (KDP) crystals for virgin and shock wave loaded samples. Rhodamine B and Methylene blue dyes are selected as dopants to be doped with KDP crystal for the present investigation. The test crystals of pure and doped KDP crystals are grown by slow evaporation technique and cut and polished crystals of (200) face are used for the present investigation. Table-top pressure driven shock tube is utilized for the shock wave generation and the used functional Mach number is 1.7. Virgin and shock wave loaded test crystals’ surface morphology, structural properties and optical transmissions are observed using optical microscope, powder X-ray diffractometer and UV-Visible spectrometer, respectively. Crystalline nature and optical transmission of pure and doped KDP crystals are found to have reduced by the impact of shock waves. It occurs due to the enhancement of defect concentration on the surface of the test crystals. From the observed results, we assert that the pure KDP crystal is relatively more stable to shock wave induced damage compared to doped KDP crystals as reflected by structural and optical studies.

In this research article, the authors pay attention to investigate the effect of structural and dielectric properties of ammonium dihydrogen phosphate (ADP) crystal under pre and post shock loaded conditions. A shock wave of Mach number 1.9 was utilized for the present investigation which was generated by a table-top pressure driven shock tube. The crystalline nature and grain size variations were estimated by powder X-ray diffraction technique. The grain size of post shock wave loaded ADP crystal is found to be larger than that of the pre shock wave loaded ADP crystal. The dielectric properties of the pre and post shock loaded crystals were analyzed by impedance analyzer as a function of frequency (1 kHz–1 MHz) at ambient temperature. The dielectric constant is observed to be varying from 346 to 362 at the frequency of 400 kHz for pre and post shock wave loaded ADP crystals, respectively. The obtained results suggest that shock waves can be an alternate tool to tailor the physical properties of materials without creating any change in the original crystal system and surface morphology.

We describe the investigation into tailoring the optical properties of ammonium dihydrogen phosphate (ADP) crystal by the influence of mild shock waves (Mach number 1.7) produced by a shock tube. An ADP crystal was grown by employing the Sankaranarayana–Ramasamy method with (101) orientation. The test crystal was subjected to different numbers of shock pulses such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and 13, respectively. Pre- and post-shock wave-loaded test crystals were experimented with a ultraviolet-visible spectrometer for recording the optical transmission. From the observed results, it is known that, on increasing shock pulses, optical transmission is enhanced from 55% to 66% in such a way that optimization is attained. Thereafter, it reduces to 47% by further increasing the number of applied shock waves. Following the optical transmission, optical constants such as extinction coefficient, optical density, skin depth, real and imaginary parts of the dielectric constant, optical conductivity, and electrical conductivity are also greatly altered if the ADP crystal is exposed to shock pulses. From this experiment, an alternative way to boost the optical properties of an ADP crystal without modifying the original crystal system and without adding any dopants is proposed.

A systematic investigation of shock wave-induced defect engineering on optical transport properties of triglycine sulfate (TGS) crystalline material is carried out under shock waves of Mach number 1.7 with a different number of shock pulses. Surface morphological changes and defect concentration are evaluated by the optical microscopic technique. Optical transmission of pre- and postshock wave-treated TGS crystal is analyzed using UV–visible spectrometer over the range between 200 and 800 nm. Unexpectedly, during the shock wave impact conditions, the test crystal exhibits vulnerability due to defects on its surface and it is confirmed by optical micrographs. Optical transmission is continually reduced while the number of shock pulses is increased due to the formation of defects on the surface of the test sample. Followed by the observation of optical transmission, optical constants and band gap energies are also calculated. The obtained results clearly show that surface morphology and optical transport properties of TGS crystal are greatly affected by the impact of shock waves.