Publications
Time-dependent POVM reconstruction for single-photon avalanche photo diodes using adaptive regularization
| Author | Fitzke, Erik; Krebs, Robin; Haase, Thorsten; Mengler, Max; Alber, Gernot; Walther, Thomas |
|---|---|
| Date | 2022 |
| Type | Journal Article |
| Abstract | We report on the first realization of time-dependent quantum detector tomography for commercially available InGaAs avalanche photo detectors. For the construction of appropriate time-dependent POVMs from experimentally measured data, we introduce a novel scheme to calculate the weight of the regularization term based on the amount of measured data. We compare our POVM-based results with the theoretical predictions of the previously developed model by Gouzien et al (2018 Phys. Rev. A 98 013833). In contrast to our measurement-based construction of a time-dependent POVM for photon detectors, this previous investigation extends a time-independent POVM to a time-dependent one by including effects of detector timing jitter and dead time on the basis of particular model assumptions concerning the inner physical mechanisms of a photon detector. Our experimental results demonstrate that this latter approach is not sufficient to completely describe the observable properties of our InGaAs avalanche photo detectors. Thus, constructing the time-dependent POVM of a detector by direct quantum tomographic measurements can reveal information about the detector's interior that may not easily be included in time-independent POVMs by a priori model assumptions. |
| In | New Journal of Physics |
| Publisher | IOP Publishing |
| Url | https://tubiblio.ulb.tu-darmstadt.de/id/eprint/131445 |
