Atomic cell, atomic resonance transition device, atomic oscillator, electronic apparatus, and moving object

1. An atomic resonance transition device comprising:

an atomic cell including:

a pair of windows;

a body disposed between the pair of windows and forming an inner space with the pair of windows; and

metal atoms sealed within the inner space,

wherein the inner space has lengths L1 and L2 in directions perpendicular to each other in a cross-section of the inner space intersecting a direction in which the pair of windows are arranged, and

L 2/ L 1≧1.1,

wherein a longitudinal portion of the inner space having the cross-section extends in the direction in which the pair of windows are arranged; and

a light emitting unit that emits light including a pair of resonance light beams for resonating the metal atoms toward the atomic cell,

wherein the atomic cell is configured to pass the light from the light emitting unit directly through the inner space without reflecting the light again through the inner space,

wherein the longitudinal portion includes a metal reservoir at which liquid or solid metal atoms are disposed at one end in a longitudinal direction, and

wherein a distance between an inner wall surface of the body and the light is D1, and a distance between the liquid or solid metal atoms disposed at the metal reservoir and the light is D2, and

2× D 1≦ D 2.

2. The atomic cell according to claim 1 , wherein L2 is constant over an entirety of the inner space in the direction in which the pair of windows are arranged.

3. The atomic cell according to claim 1 , wherein L2 is measured at an end or in a middle of the inner space in the direction in which the pair of windows are arranged.

4. The atomic cell according to claim 1 , wherein the cross-section of the inner space is elliptical.

5. The atomic cell according to claim 1 , wherein L1 is in a range of 0.5 mm≦L1≦3 mm.

6. The atomic resonance transition device according to claim 1 , wherein a center of the longitudinal portion and a center of the light are deviated relative to each other in the longitudinal direction when viewed from the direction in which the pair of windows are arranged.

7. The atomic resonance transition device according to claim 1 , wherein the D1 is in a range of 0.05 mm≦D1≦1 mm.

8. An atomic oscillator comprising the atomic resonance transition device according to claim 1 .

9. An electronic apparatus comprising the atomic resonance transition device according to claim 1 .

10. A moving object comprising the atomic resonance transition device according to claim 1 .

11. An atomic resonance transition device comprising:

an atomic cell that includes an inner space in which metal atoms are sealed; and

a light emitting unit that emits light including a pair of resonance light beams for resonating the metal atoms toward the atomic cell in a first direction,

wherein the atomic cell is configured to pass the light from the light emitting unit directly through the inner space without reflecting the light again through the inner space,

wherein the inner space includes a metal reservoir at which liquid or solid metal atoms are disposed, the metal reservoir being at part of a wall surface of the inner space, and the wall surface extends along the first direction, and

wherein a distance between the wall surface of the inner space and the light is D1, and a distance between the liquid or solid metal atoms disposed at the metal reservoir and the light is D2, and

2× D 1≦ D 2.

12. The atomic cell according to claim 11 , wherein a longitudinal portion of the inner space having a cross-section extends in as direction in which a pair of windows, which are provided at both sides of the atomic cell, are arranged.

13. The atomic cell according to claim 11 , wherein

a cross-section of the inner space is elliptical.