Ionisierung an einem pyroelektrischen Material

https://www.google.de/patents/US7791019
2008 California Institute Of Technology

Unter Normaldruck funktionierende Ionisationsquelle mithilfe von pyroelektrischen Effekt.
Nutzung in Massenspektrometer, also Kleinstmengen


BACKGROUND OF THE INVENTION
The pyroelectric effect is observed when a pyroelectric material is subjected to a change in temperature.
By way of example, a thin, parallel-sided sample of material, such as a tourmaline crystal can be cut so that its crystallographic symmetry axis is perpendicular to the flat surfaces.
The unit cells of pyroelectric materials so cut have a net dipole moment oriented along the direction normal to the flat surfaces (or along the crystallographic symmetry axis).
The dipole moment per unit volume of the material is called the spontaneous polarization PS. PS is always nonzero in a pyroelectric material. PS exists in the absence of an applied electric field and can be thought of as a layer of bound charge on each flat surface of the sample, one face having a net positive charge and the other a net negative charge.
..
There is a need for a compact, robust, ambient pressure ion source that can be used in mass spectrometry.

Dadurch bekommt man wie beim Gaschromatograph eine Aufteilung der Bestandteile nach Zeit