Photodetector and photodetection system

A photodetector, comprising:

• a first electrode;
• a second electrode;
• and
• a stacked member, at least a part of the stacked member being between the first electrode and the second electrode;
• the stacked member including a detection layer and a photonic crystal layer,
• the detection layer including:
• a plurality of first semiconductor films;
• and
• a second semiconductor film provided between the plurality of first semiconductor films,
• the photonic crystal layer being configured to supply the detection layer with a detection target light being incident on the photonic crystal layer,
• an electrical signal generated between the first electrode and the second electrode is configured to change according to a detection target light being incident on the photonic crystal layer, and
• a first number of the plurality of first semiconductor films is not less than 2 and not more than 10.

A photodetection system comprising:

• a first light-emitter configured to emit a first light;
• and
• a first detector configured to detect a detection target light based on the first light,
• each of the first light-emitter and the first detector including a stacked member including a stacked body,
• the stacked body including:
• a plurality of first semiconductor films;
• and
• a second semiconductor film provided between the plurality of first semiconductor films,
• a first number of the plurality of first semiconductor films included in the stacked body of the first detector being smaller than a second number of the plurality of first semiconductor films included in the stacked body of the first light-emitter.

A photodetector, comprising:

• a first detector,
• the first detector including a stacked member including a detection layer 10,
• the detection layer including:
• a plurality of first semiconductor films, and
• a second semiconductor film provided between the plurality of first semiconductor films,
• the stacked member further including a photonic crystal layer,
• the photonic crystal layer being configured to a supply detection target light being incident on the photonic crystal layer to the detection layer,
• the first detector further including a first electrode and a second electrode,
• at least a part of the stacked member being provided between the first electrode and the second electrode,
• an electrical signal generated between the first electrode and the second electrode is configured to change in response to detection target light being incident on the photonic crystal layer, and
• the detection layer including a quantum cascade active layer.