The technique introduced herein decouples the traditional relationship between bandwidth and responsivity, thereby providing a more flexible and wider photodetector design space. In certain embodiments of the technique introduced here, a photodetector device includes a first mirror, a second mirror, and a light absorption region positioned between the first and second reflective mirrors. For example, the first mirror can be a partial mirror, and the second mirror can be a high-reflectivity mirror. The light absorption region is positioned to absorb incident light that is passed through the first mirror and reflected between the first and second mirrors. The first mirror can be configured to exhibit a reflectivity that causes an amount of light energy that escapes from the first mirror, after the light is reflected back by the second mirror, to be zero or near zero.