Quantum interference unit, quantum interference device, atomic oscillator, electronic apparatus, and moving object

• US 9,342,269 B2
• Filed: 01/27/2015
• Issued: 05/17/2016
• Est. Priority Date: 01/28/2014
• Status: Active Grant

• Current Assignee: Microchip Technology Incorporated
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Hashi, Yukihiro
• Primary Examiner(s): Gannon, Levi
• Application Number:
  US14/606,327
• Publication Number:
  US 20150214895A1
• Time in Patent Office: 476 Days
• Field of Search: 331/3, 331 68- 70, 331/94.1
• US Class Current: 1/1
• CPC Class Codes: G04F 5/14 using atomic clocks
• CPC Class Codes: G06F 5/14 for overflow or underflow handling, e.g. full or empty flags
• CPC Class Codes: H03B 1/04 Reducing undesired oscillations, e.g. harmonics
• CPC Class Codes: H03B 17/00 Generation of oscillations using radiation source and detector, e.g. with interposed variable obturator
• CPC Class Codes: H03L 7/26 using energy levels of molecules, atoms, or subatomic particles as a frequency reference

Abstract

An atomic oscillator includes: a gas cell which houses metal atoms; a heater which adjusts a temperature of the gas cell; and a package which houses the gas cell and the heater. The package includes a non-magnetic metal layer.

Claims

1. A quantum interference unit comprising:

a gas cell which houses metal atoms;

a temperature adjustment element operatively associated with the gas cell to adjust a temperature of the gas cell; and

a package housing the gas cell and the temperature adjustment element, the package including a lid formed of a non-magnetic metal layer, wherein

the package further includes a coating layer coated over the non-magnetic metal layer, the coating layer being a different material than the non-magnetic metal layer, and

the coating layer contains a non-magnetic metal.

2. The quantum interference unit according to claim 1, further comprising a coil which is arranged on an exterior of the package and applies a magnetic field to the metal atoms.

3. The quantum interference unit according to claim 2, further comprising a magnetic shield which houses the package and the coil.

4. The quantum interference unit according to claim 1, wherein an interior of the package is at a negative atmospheric pressure.

5. The quantum interference unit according to claim 4, wherein a brazing material seals the lid of the package to a base.

6. The quantum interference unit according to claim 5, wherein a melting point of the brazing material is below 300°

C.

7. The quantum interference unit according to claim 5, wherein the brazing material contains gold and tin.

8. The quantum interference unit according to claim 1, wherein the coating layer contains phosphorus.

9. The quantum interference unit according to claim 8, wherein a content of the phosphorus in the coating layer is 8% by weight or more.

10. The quantum interference unit according to claim 1, wherein the coating layer contains palladium.

11. A quantum interference device comprising:

the quantum interference unit according to claim 1; and

a control unit controlling the quantum interference unit.

12. An atomic oscillator comprising:

the quantum interference unit according to claim 1; and

a control unit controlling the quantum interference unit.

13. An electronic apparatus comprising:

the quantum interference unit according to claim 1; and

a control unit controlling the quantum interference unit.

14. A moving object comprising:

the quantum interference unit according to claim 1; and

a control unit controlling the quantum interference unit.

15. A quantum interference unit comprising:

a gas cell which houses metal atoms;

a temperature adjustment element operatively associated with the gas cell;

a package housing the gas cell and the temperature adjustment element, the package including a base sealed to a lid with a brazing material; and

a coating layer coated over the lid, the coating layer being a different material than the lid,

wherein a non-magnetic metal layer extends along an entirety of the lid, and

the coating layer contains a non-magnetic metal.

16. The quantum interference unit according to claim 15, wherein a melting point of the brazing material is below 300°

C.