Re: [Phys-L] Names

[Bernard Cleyet <bernardcleyet@redshift.com>]

On 2012, Jun 19, , at 13:38, John Denker wrote:

> I suppose there must be analogous practical applications for the
> D-field, although I can't think of any

An exact analogy?  Practical?



2.3 Dielectric hvsteresis
The electric field E and the polarization P are connected in
a dielectric medium by the relation:
D - ε()E + P (2.1)
in which ε() is the permittivity of free space and D is the
electric displacement. For a ferroelectric material like
PZT, however, P is itself a function of E as shown in
Fig.2.3. In this figure, the hysteresis effect, familiar from
ferromagnetics, is quite evident. If an initially unpolarized
sample of PZT is subjected to an increasing electric field
at a temperature slightly below its Curie point, the dipoles
become increasing aligned with the field and the polarization
will follow the `initial curve' shown in Fig.2.3.
When the field has increased beyond a certain value, no
further increase in polarization will be observed because
the dipoles are then all aligned with the field. The
material is then said to have reached its saturation
polarization Ps*

https://docs.google.com/viewer?a=v&q=cache:F5uEoO6gMcUJ:www.morganelectroceramics.com/download.php?2f665068426577725632524b33756a4f646e393663306166637856712b4c62417570786b685a7a49474c667278673d3d/?301Redirect+%22dielectric+hysteresis%22+wikipedia&hl=en&gl=us&pid=bl&srcid=ADGEEShzPAP1Dy4BTLVyEFcxZSlYSf7YDEoOnuIuP6Kev5cexg_6weodcLtKKw5uyViIQjWjzGe3oSd8On9a752y9ERT-0wIqJotWQY8X9T4CIwV-kQLHyU7XdkVQcKsk8Cvo5Aj0coW&sig=AHIEtbRUpCi0lLl9tBFWAILQmKH283uM-g

bc   back in ca 1963 built an HV ramp to show the saturation, etc.  of Ba Ti Ox  caps.