Abstract
Conventional X-ray sources are bulky and require a high DC voltage. Pyroelectric X-ray generator technology has enabled us to develop portable, low-voltage X-ray sources for use in materials analysis, imaging, and other applications. The development of intense and reliable sources of charged particle beams is a current within accelerator physics in its own right. Changing the temperature of a single crystal of Lithium Tantalate (LiTaO3) in moderate vacuum conditions leads to generation of a strong electric field. If a metal target is placed nearby facing the crystal, the uncompensated polarization generated during the heating or cooling of the crystal causes the ejection of electrons from either the dielectric layer on the surface of the crystal or from the metal target depending on the polarity. These electrons are than accelerated by the strong electric field gaining an energy of up to 100 keV. The energy of these electrons can be determined by measuring the end-point energy of the X-ray spectrum that results from the interaction of the electrons with the target.
It has been experimentally confirmed that a pyroelectric crystal installed in a chamber with a residual gas pressure of about 2 mTorr could be used to generate electrons with energy of up to 35 keV. Here, we present studies of the features of the electron flux in a pyroelectric accelerator and how they are affected by the pressure of the residual gas, and the distance between the crystal and the target. The connection between monoenergetic electron production in a pyroelectric generator and avalanche discharge in a gas is discussed. It is demonstrated that using a pair of crystals enables us to double the acceleration potential. Using the same setup an unknown sample was fluoresced using a pyroelectric accelerator in order to analyse its elemental content. In this report we demonstrate how pyroelectric accelerators can complement conventional X-ray tubes and radioisotopes or even large central facilities. Pyroelectric X-ray generator technology is currently being developed to provide a reliable, compact, stable, and reproducible X-ray source with controllable parameters, which does not require a high-voltage DC voltage or the use of hazardous (radioactive) materials.
It has been experimentally confirmed that a pyroelectric crystal installed in a chamber with a residual gas pressure of about 2 mTorr could be used to generate electrons with energy of up to 35 keV. Here, we present studies of the features of the electron flux in a pyroelectric accelerator and how they are affected by the pressure of the residual gas, and the distance between the crystal and the target. The connection between monoenergetic electron production in a pyroelectric generator and avalanche discharge in a gas is discussed. It is demonstrated that using a pair of crystals enables us to double the acceleration potential. Using the same setup an unknown sample was fluoresced using a pyroelectric accelerator in order to analyse its elemental content. In this report we demonstrate how pyroelectric accelerators can complement conventional X-ray tubes and radioisotopes or even large central facilities. Pyroelectric X-ray generator technology is currently being developed to provide a reliable, compact, stable, and reproducible X-ray source with controllable parameters, which does not require a high-voltage DC voltage or the use of hazardous (radioactive) materials.
| Original language | English |
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| Publication status | Published - 7 Mar 2025 |