Abstract: Embodiments include systems and methods for increasing frequency offset tracking in clock data recovery (CDR) systems. For example, in asynchronous clocking environments, the receiver-side clock frequency can be offset from the transmitter-side clock. While traditional CDR systems can handle some amount of offset, they are typically ineffective at accurately adapting the receiver-side clocking to an optimal data sampling rate when the offset is excessive. Embodiments include a CDR frequency offset adaptation loop that generates an adaptation signal, which can be monitored to detect an adaptation error arising from excessive frequency offset. In response to the detecting, an offset seed can be selected and injected into the frequency offset adaptation loop, thereby reinitializing the frequency offset adaptation loop with a less stressful seed.

Abstract: Apparatuses and systems for photon detection can include a first optical sensing structure structured to absorb light at a first optical wavelength; and a second optical sensing structure engaged with the first optical sensing structure to allow optical communication between the first and the second optical sensing structures. The second optical sensing structure can be structured to absorb light at a second optical wavelength longer than the first optical wavelength and to emit light at the first optical wavelength which is absorbed by the first optical sensing structure. Apparatuses and systems can include a bandgap grading region.

Abstract: Apparatuses and systems for photon detection can include a first optical sensing structure structured to absorb light at a first optical wavelength; and a second optical sensing structure engaged with the first optical sensing structure to allow optical communication between the first and the second optical sensing structures. The second optical sensing structure can be structured to absorb light at a second optical wavelength longer than the first optical wavelength and to emit light at the first optical wavelength which is absorbed by the first optical sensing structure. Apparatuses and systems can include a bandgap grading region.