Semiconductor laser and atomic oscillator
A semiconductor laser including: a first mirror layer; a second mirror layer; an active layer, a current confinement layer, a first region, and a second region, in which the first mirror layer, the second mirror layer, the active layer, the current confinement layer, the first region, and the second region constitute a laminated body, the first region and the second region constitute an oxidized region of the laminated body, in a plan view, the laminated body includes a first part, a second part, and a third part disposed between the first part and the second part and resonating light generated in the active layer, and in a plan view, at least at a part of the third part, W 1 >W 3 and W 2 >W 3 , W 1 is a width of the oxidized region of the first part, W 2 is a width of the oxidized region of the second part, and W 3 is a width of the oxidized region of the third part.
1. A semiconductor laser comprising:
a first mirror layer;
a second mirror layer;
an active layer disposed between the first mirror layer and the second mirror layer;
a current confinement layer disposed between the first mirror layer and the second mirror layer;
a first region provided continuously with the first mirror layer and including a plurality of first oxidized layers; and
a second region provided continuously with the second mirror layer and including a plurality of second oxidized layers, wherein
the first mirror layer, the second mirror layer, the active layer, the current confinement layer, the first region, and the second region constitute a laminated body,
the first region and the second region constitute an oxidized region of the laminated body,
in a plan view, the laminated body includes a first part, a second part, and a third part disposed between the first part and the second part and resonating light generated in the active layer, and
in a plan view, at least at a part of the third part,
W1>W3 and W2>W3 (1)
W 1 is a width of the oxidized region of the first part,
W 2 is a width of the oxidized region of the second part, and
W 3 is a width of the oxidized region of the third part.
2. The semiconductor laser according to claim 1 , wherein W 3 =0.
3. The semiconductor laser according to claim 1 , wherein W 3 >0.
4. The semiconductor laser according to claim 1 , wherein
the expression (1) is satisfied at the entire third part.
5. The semiconductor laser according to claim 1 , wherein
the expression (1) is satisfied at a part of the third part.
6. The semiconductor laser according to claim 1 , wherein
the laminated body includes a fourth part,
a gap is provided between a first side surface of the third part and a second side surface of the fourth part, and
the expression (1) is satisfied at a part that faces the gap of the first side surface.
7. The semiconductor laser according to claim 6 , wherein
the fourth part includes a third oxidized layer, and the current confinement layer and the third oxidized layer are continuous with each other.
8. The semiconductor laser according to claim 1 , further comprising:
a layer that covers a part of the third part, wherein
the expression (1) is satisfied at the part of the third part that covered by the layer.
9. An atomic oscillator comprising:
a semiconductor laser;
an atom cell irradiated with light emitted from the semiconductor laser and containing alkali metal atoms; and
a light receiving element that detects intensity of light transmitted through the atom cell and outputs a detection signal, wherein
the semiconductor laser includes
a first mirror layer,
a second mirror layer,
an active layer disposed between the first mirror layer and the second mirror layer,
a current confinement layer disposed between the first mirror layer and the second mirror layer,
a first region provided continuously with the first mirror layer and including a plurality of first oxidized layers, and
a second region provided continuously with the second mirror layer and including a plurality of second oxidized layers,
the first mirror layer, the second mirror layer, the active layer, the current confinement layer, the first region, and the second region constitute a laminated body,
the first region and the second region constitute an oxidized region of the laminated body,
in a plan view, the laminated body includes a first part, a second part, and a third part disposed between the first part and the second part and resonating light generated in the active layer, and
in a plan view, at least at a part of the third part,
W1>W3 and W2>W3 (1)
W 1 is a width of the oxidized region of the first part,
W 2 is a width of the oxidized region of the second part, and
W 3 is a width of the oxidized region of the third part.