Enhanced signal amplitude in acoustic-magnetomechanical EAS marker

1. A method for making a marker, comprising:

obtaining a resonator material which has been annealed under a tensile force selected to provide a maximum resonant amplitude at a bias field H max ; and

reducing a value of an operating bias field H operating in said marker to a value less than a value of said bias field H max by selectively modifying a spacing between said resonator material and said bias material arranged in a stacked configuration; and

partially de-gaussing a bias material subsequent to being fully saturated and prior to when the marker is attached to an article to be protected or tracked.

2. The method according to claim 1 , wherein the value of the operating bias field H operating is further reduced by selectively modifying a geometry of the bias material which is to be disposed in a housing of said marker, said geometry is selectively modified by changing a width of said bias material having a rectangular shape.

3. The method according to claim 1 , wherein the value of the operating bias field H operating is further reduced by selectively modifying a geometry of the bias material which is to be disposed in a housing of said marker, said geometry is selectively modified by changing a thickness of said bias material having a rectangular shape.

4. The method according to claim 1 , wherein said spacing is selectively modified by disposing a spacer between said resonator material and said bias material arranged in said stacked configuration.

5. The method according to claim 1 , wherein said bias material is partially de-gaussed through an application of a reverse magnetic field to said marker.

6. The method according to claim 1 , wherein said marker is an Electronic Article Surveillance label attachable to an article to be protected from unauthorized removal from a particular area.

7. The method according to claim 1 , wherein said resonator material is made at least from Iron, Nickel and cobalt.

8. The method according to claim 1 , wherein a signal amplitude of said marker is increased by an amount equal to or greater than half an original signal amplitude value as a result of said reducing.

9. The method according to claim 1 , wherein a magnetic clamping of said resonator material by said bias material is decreased as a result of said reducing.

10. A method for making a marker, comprising:

obtaining a resonator material which has been annealed under a tensile force selected to provide a bias field H max in said marker;

disposing the resonator material and bias material in a stacked arrangement within a housing to form said marker;

applying a magnetic field to said marker to saturate the bias material; and

applying a reverse magnetic field to said marker to further reduce said value of said operating bias field H operating in said marker prior to when the marker is attached to an article to be protected or tracked.

11. The method according to claim 10 , further comprising selectively modifying a geometry of a bias material such that a value of an operating bias field H operating in said marker is reduced.

12. The method according to claim 10 , further comprising selectively modifying a spacing between said resonator material and said bias material arranged in a stack.

13. A marker, comprising:

a resonator material which has been annealed under a tensile force selected to provide a maximum resonant amplitude at a bias field H max ; and

a bias material which has been processed to provide a value of an operating bias field H operating in said marker which is less than a value of said bias field H max , where said bias material comprises at least one of the following features:

a selectively modified spacing from said resonator material; and

a partially reduced remnant magnetic field which was obtained by partially de-gaussing the bias material prior to when the marker is attached to an article to be protected or tracked.

14. The marker according to claim 13 , wherein the bias material has a selectively modified geometry, said geometry selectively modified by changing a width of said bias material having a rectangular shape.

15. The marker according to claim 13 , wherein the bias material has a selectively modified geometry, said geometry is selectively modified by changing a thickness of said bias material having a rectangular shape.

16. The marker according to claim 13 , wherein said spacing is selectively modified by disposing a spacer between said resonator material and said bias material arranged in a stacked configuration.

17. The marker according to claim 13 , wherein said remnant magnetic field is partially reduced through an application of a reverse magnetic field to said marker.

18. The marker according to claim 17 , wherein said reverse magnetic field is applied to said marker subsequent to an application of a magnetic field thereto to saturate said bias material.

19. The marker according to claim 13 , wherein said marker is an Electronic Article Surveillance label attachable to an article to be protected from unauthorized removal from a particular area.

20. A marker, comprising:

a housing;

a resonator material disposed in said housing which has been annealed under a tensile force selected to provide a maximum resonant amplitude at a bias field H max in said marker; and

a bias material disposed in said housing in a stacked arrangement with said resonator material;

wherein a magnetic field has been applied to said marker to saturate the bias material, and a reverse magnetic field has been applied to said marker prior to when the marker is attached to an article to be protected or tracked and so that a value of an operating bias field H operating in said marker is reduced as compared to said bias field H max .