arXiv subjects

Oliver Schulz

Publications and source records attributed to Oliver Schulz.

21 records · Page 2Linked to original sources

arXiv2018

Alpha-event and surface characterisation in segmented true-coaxial HPGe detectors

A detailed study of alpha interactions on the passivation layer on the end-plate of a true-coaxial high-purity germanium detector is presented. The observation of alpha events on such a surface indicates an unexpectedly thin so-called "dead layer" of less than 20 μm thickness. In addition, the influence of the metalisation close to the end-plate on the time evolution of the output pulses is discussed. The results indicate that alpha contamination can result in events which could be mistaken as signals for neutrinoless double beta decay and provide some guidance on how to prevent this.

physics.ins-det↗

arXiv2014

Pulse-shape discrimination of surface events in CdZnTe detectors for the COBRA experiment

Events near the cathode and anode surfaces of a coplanar grid CdZnTe detector are identifiable by means of the interaction depth information encoded in the signal amplitudes. However, the amplitudes cannot be used to identify events near the lateral surfaces. In this paper a method is described to identify lateral surface events by means of their pulse shapes. Such identification allows for discrimination of surface alpha particle interactions from more penetrating forms of radiation, which is particularly important for rare event searches. The effectiveness of the presented technique in suppressing backgrounds due to alpha contamination in the search for neutrinoless double beta decay with the COBRA experiment is demonstrated.

nucl-ex↗

arXiv2003

Ascertaining the Values of $σ_x$, $σ_y$, and $σ_z$ of a Polarization Qubit

In the 1987 spin retrodiction puzzle of Vaidman, Aharonov, and Albert one is challenged to ascertain the values of $σ_x$, $σ_y$, and $σ_z$ of a spin-1/2 particle by utilizing entanglement. We report the experimental realization of a quantum-optical version in which the outcome of an intermediate polarization projection is inferred by exploiting single-photon two-qubit quantum gates. The experimental success probability is consistently above the 90.2% threshold of the optimal one-qubit strategy, with an average success probability of 95.6%.

quant-ph↗