Claims
- 1. A ferroelectric material, comprising:
a perovskite alloy comprising stacked planes of the form (A′A″A′″ . . . )(B′x′(k)B″x″(k)B′″x′″(k) . . . )X3, wherein A′,A″,A′″, . . . , B′,B″,B′″, . . . and X3 represent atomic species, wherein at least two of B′, B″, B′″, . . . belong to different columns of the periodic table and wherein x′(k), x″(k), x′″(k), . . . are modulated parameters yielding the relative concentration of the B′, B″, B′″, . . . atoms, respectively, in each plane, k, of said alloy; wherein said alloy is atomically ordered along a direction that is not the direction of polarization of the disordered alloy; wherein said planes are stacked with a short stacking period; and wherein said modulated parameters x′(k), x″(k), x′″(k), . . . are selected to obtain at a specific temperature dielectric and piezoelectric properties of said alloy that are substantially enhanced over the dielectric and piezoelectric properties of the disordered alloy, said specific temperature being selected from any temperature less than the Curie temperature of the disordered alloy.
- 2. The ferroelectric material of claim 1, wherein said stacking period is a four-plane period.
- 3. The ferroelectric material of claim 1, wherein said A′ atom is lead, with no other A site atoms.
- 4. The ferroelectric material of claim 1, wherein said B′ atom is Scandium.
- 5. The ferroelectric material of claim 1, wherein said B″ atom is Niobium.
- 6. The ferroelectric material of claim 1 having no B site alloying elements other than Scandium and Niobium.
- 7. The ferroelectric material of claim 1, where said X atom is oxygen.
- 8. The ferroelectric material of claim 1, wherein said direction along which said alloy is atomically ordered is along the [001] direction.
- 9. A ferroelectric material, comprising:
a perovskite alloy comprising stacked planes of the form (A′x′(k)A″x″(k)A′″x′″(k) . . . )(B′B″B′″ . . . )X3, wherein A′,A″,A′″, . . . , B′,B″,B′″, . . . and X3 represent atomic species, wherein at least two of A′, A″, A′″, . . . belong to different columns of the periodic table and wherein x′(k), x″(k), x′″(k), . . . , are modulated parameters yielding the relative concentration of the A′, A″, A′″, . . . atoms, respectively, in each plane, k, of said alloy; wherein said alloy is atomically ordered along a direction that is not the direction of polarization of the disordered alloy; wherein said planes are stacked with a short stacking period; and wherein said modulated parameters x′(k), x″(k), x′″(k), . . . are selected to obtain at a specific temperature dielectric and piezoelectric properties of said alloy that are substantially enhanced over the dielectric and piezoelectric properties of the disordered alloy, said specific temperature being selected from any temperature less than the Curie temperature of the disordered alloy.
- 10. The ferroelectric material of claim 9, wherein said stacking period is a four-plane period.
- 11. The ferroelectric material of claim 9, where said X atom is oxygen.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 60/401,995 filed Aug. 8, 2002.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This invention was made using support from agencies of the United States Government: Office of Naval Research Grant Nos. N00014-00-1-0542 and N00014-01-1-0600 and National Science Foundation Grant No. DMR-9983678. The government has certain rights in the invention.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60401995 |
Aug 2002 |
US |