Control Electronics For Semiconductor Spin Qubits

Future universal quantum computers solving problems of practical relevance are expected to require at least $10^6$ qubits, which is a massive scale-up from the present numbers of less than 50 qubits operated together. Out of the different types of qubits, solid state qubits are considered to be viable candidates for this scale-up, but interfacing to and controlling such a large number of qubits is a complex challenge that has not been solved yet. One possibility to address this challenge is to use qubit control circuits located close to the qubits at cryogenic temperatures. In this work we evaluate the feasibility of this idea, taking as a reference the physical requirements of a two-electron spin qubit and the specifications of a standard 65 nm complementary metal-oxide-semiconductor (CMOS) process. Using principles and flows from electrical systems engineering we provide realistic estimates of the footprint and of the power consumption of a complete control-circuit architecture. Our results show that with further research it is possible to provide scalable electrical control in the vicinity of the qubit, with our concept

Read-out electronics for digital silicon photomultiplier modules

A new kind of a PET-Scanner (PET = positron emission tomography) for plant research is developed asa joint project of the Forschungszentrum Jülich and Philips Digital Photon Counting (PDPC). Thisscanner will utilize digital silicon photomultiplier (dSiPM) for plant phenotyping for the very first time.The goal of this work is to get a further knowledge of the operation of digital silicon photomultiplier.On this account a test-facility for this new photo detectors has been installed at the central instituteof engineering, electronics and analytics (ZEA-2 electronic systems) to determine the usage of thissensors, having regard to use them as scintillation detectors in a PET-Scanner later on.This work has its focus on the development of a fast read-out electronic for the used photo sensorsDPC3200-22-44. As there will be high data rates a fast USB 3.0 interface has been used. All thenecessary processing and data handling has been implemented in a state of the art FPGA

phenoPET: A dedicated PET Scanner for Plant Research based on digital SiPMs

In the frame of the German Plant Phenotyping Project (DPPN) we developed a novel PET scanner. In contrary to a clinical or preclinical PET scanner the detector rings of the Plant System are oriented in a horizontal plane. The final system will be equipped with three rings covering a Field of View (FOV) of 18 cm diameter and 20 cm axial height. One detector ring is formed by 12 modules. Each module contains four 8×8 pixel digital SiPM devices DPC-3200-22-44 (Philips Digital Photon Counting) connected to a PCB and four scintillator matrices with 16×16 individual LYSO scintillators. Crystal size is 1.85×1.85×10 mm3. The matrices are composed with both reflective and transparent contact faces between the crystals in order to optimize crystal identification. A cooling system keeps the detectors below 5°C and limits the dark count rate. Data are already preprocessed by the Cyclone FPGA (Altera) in the module and transmitted from there at 50MiB/s to the base board. The base board collects the data from all modules and allows coincidence detection performed on a Kintex-7 FPGA (Xilinx). Finally the data link to the computer system for image reconstruction is realized via an USB 3.0 connection. Due to the fast photodetectors the system is dedicated to work with rather high activities. Preliminary measurements showed a coincidence peak of 250 ps FWHM between two detector elements and an energy resolution ΔE/E = 12%. This paper will present first results from a one ring system with a FOV of 18 cm diameter and 6.5 cm axial height

Neutrino Physics with JUNO

The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multi-purposeunderground liquid scintillator detector, was proposed with the determinationof the neutrino mass hierarchy as a primary physics goal. It is also capable ofobserving neutrinos from terrestrial and extra-terrestrial sources, includingsupernova burst neutrinos, diffuse supernova neutrino background, geoneutrinos,atmospheric neutrinos, solar neutrinos, as well as exotic searches such asnucleon decays, dark matter, sterile neutrinos, etc. We present the physicsmotivations and the anticipated performance of the JUNO detector for variousproposed measurements. By detecting reactor antineutrinos from two power plantsat 53-km distance, JUNO will determine the neutrino mass hierarchy at a 3-4sigma significance with six years of running. The measurement of antineutrinospectrum will also lead to the precise determination of three out of the sixoscillation parameters to an accuracy of better than 1\%. Neutrino burst from atypical core-collapse supernova at 10 kpc would lead to ~5000inverse-beta-decay events and ~2000 all-flavor neutrino-proton elasticscattering events in JUNO. Detection of DSNB would provide valuable informationon the cosmic star-formation rate and the average core-collapsed neutrinoenergy spectrum. Geo-neutrinos can be detected in JUNO with a rate of ~400events per year, significantly improving the statistics of existing geoneutrinosamples. The JUNO detector is sensitive to several exotic searches, e.g. protondecay via the $p\to K^++\bar\nu$ decay channel. The JUNO detector will providea unique facility to address many outstanding crucial questions in particle andastrophysics. It holds the great potential for further advancing our quest tounderstanding the fundamental properties of neutrinos, one of the buildingblocks of our Universe

Detection of the Diffuse Supernova Neutrino Background with JUNO

As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

Characterization of the JUDIDT Readout Electronics for Neutron Detection

The Group for the development of neutron and gamma detectors in the Central Institute of Engineering, Electronics and Analytics (ZEA-2) at Forschungszentrum Jülich (FZJ) has developed, in collaboration with European institutes, an Anger Camera prototype for improving the impact point reconstruction of neutron tracks. The detector is a chamber filled with $^3He$+$CF_4$ gas for neutron capture and subsequent production of a tritium and a proton. The energy deposition by the ions gives rise to drifting electrons with an avalanche amplification as they approach a micro-strip anode structure. The scintillating light, generated during the electron drift and avalanche stage, is collected by four vacuum photomultipliers. The position reconstruction is performed via software algorithms. The JUDIDT readout electronics was modified at ZEA-2 to cope with the data acquisition requirements of the prototype. The results of the commissioning of the electronics are here presented and commented