Patent Number: 
Section: claims

1. A vapor-cell system comprising a bidirectional solid-state electrochemical charge-depletion capacitor and a vapor-cell region configured to allow at least one optical path into a vapor phase within said vapor-cell region,wherein said charge-depletion capacitor includes:(i) a first electrode disposed in contact with said vapor-cell region;(ii) a second electrode electrically isolated from said first electrode; and(iii) an ion conductor interposed between said first electrode and said second electrode,wherein said first electrode is permeable to mobile ions and/or neutral atoms formed from said mobile ions;wherein said ion conductor is ionically conductive for said mobile ions, andwherein said second electrode does not contain a second-electrode material that is capable of forming said mobile ions. 2. The vapor-cell system of claim 1, wherein said charge-depletion capacitor stores electrical charge by reduction-oxidation reactions, electrosorption, intercalation, or combinations thereof. 3. The vapor-cell system of claim 1, wherein said charge-depletion capacitor has an actuation voltage of about 100 V or less. 4. The vapor-cell system of claim 3, wherein said charge-depletion capacitor has an actuation voltage of about 10 V or less. 5. The vapor-cell system of claim 1, wherein said vapor-cell system is characterized by a vapor-cell time constant for said mobile ions of less than 1 second. 6. The vapor-cell system of claim 5, wherein said vapor-cell time constant is about 100 milliseconds or less. 7. The vapor-cell system of claim 1, wherein said vapor-cell vapor phase contains an alkali metal, an alkaline earth metal, or a combination thereof. 8. The vapor-cell system of claim 1, wherein said vapor-cell vapor phase contains mercury, ytterbium, aluminum, cadmium, or a combination thereof. 9. The vapor-cell system of claim 1, wherein said ion conductor is ionically conductive for at least one ionic species selected from the group consisting of Rb+, Cs+, Na+, K+, and Sr2+. 10. The vapor-cell system of claim 1, wherein said ion conductor is characterized by an ionic conductivity at 25° C. of about 10−7 S/cm or higher. 11. The vapor-cell system of claim 10, wherein said ion conductor is characterized by an ionic conductivity at 25° C. of about 10−5 S/cm or higher. 12. The vapor-cell system of claim 1, wherein said ion conductor contains said mobile ions. 13. The vapor-cell system of claim 1, wherein said ion conductor contains immobile ions having opposite charge of said mobile ions. 14. The vapor-cell system of claim 1, wherein said ion conductor comprises alumina, β-alumina, β″-alumina, yttria-stabilized zirconia, NASICON, LISICON, KSICON, or combinations thereof. 15. The vapor-cell system of claim 1, wherein said first electrode is fabricated from a metal selected from the group consisting of platinum, molybdenum, tungsten, and combinations thereof. 16. The vapor-cell system of claim 1, wherein said first electrode is in the form of a mesh, a grid, a porous material with open porosity, a parallel line pattern, a microwire array, a nanowire array, a lithographically patterned network, or a combination thereof. 17. The vapor-cell system of claim 1, wherein said second electrode is not in contact with said vapor-cell region. 18. The vapor-cell system of claim 1, wherein said second electrode is not permeable to said mobile ions or neutral atoms formed from said mobile ions. 19. The vapor-cell system of claim 1, wherein said second-electrode material is not capable of forming second-electrode ions, different than said mobile ions, which are mobile in said ion conductor. 20. The vapor-cell system of claim 1, wherein said second electrode is fabricated from a metal selected from the group consisting of platinum, molybdenum, tungsten, and combinations thereof. 21. The vapor-cell system of claim 1, said system further comprising an atom chip contained within said vapor-cell region. 22. The vapor-cell system of claim 1, wherein said vapor-cell system is configured to allow three optical paths into said vapor phase. 23. A magneto-optical trap apparatus, said apparatus comprising:(a) a bidirectional solid-state electrochemical charge-depletion capacitor;(b) a vapor-cell region configured to allow three orthogonal optical paths into a vapor phase within said vapor-cell region;(c) a source of laser beams configured to provide said three orthogonal vapor-cell optical paths through said vapor-cell gas phase, to trap a population of cold atoms; and(d) a magnetic-field source configured to generate magnetic fields within said vapor-cell region,wherein said charge-depletion capacitor includes:(i) a first electrode disposed in contact with said vapor-cell region;(ii) a second electrode electrically isolated from said first electrode; and(iii) an ion conductor interposed between said first electrode and said second electrode,wherein said first electrode is permeable to mobile ions and/or neutral atoms formed from said mobile ions;wherein said ion conductor is ionically conductive for said mobile ions, andwherein said second electrode does not contain a second-electrode material that is capable of forming said mobile ions. 24. An atomic-cloud imaging apparatus, said apparatus comprising:(a) a bidirectional solid-state electrochemical charge-depletion capacitor;(b) a vapor-cell region configured to allow three orthogonal optical paths into a vapor phase within said vapor-cell region;(c) a source of laser beams configured to provide said three orthogonal vapor-cell optical paths through said vapor-cell gas phase, to image a population of cold atoms; and(d) a magnetic-field source configured to generate magnetic fields within said vapor-cell region,wherein said charge-depletion capacitor includes:(i) a first electrode disposed in contact with said vapor-cell region;(ii) a second electrode electrically isolated from said first electrode; and(iii) an ion conductor interposed between said first electrode and said second electrode,wherein said first electrode is permeable to mobile ions and/or neutral atoms formed from said mobile ions;wherein said ion conductor is ionically conductive for said mobile ions, andwherein said second electrode does not contain a second-electrode material that is capable of forming said mobile ions.