A5039069955- Quantum and electron transport phenomena
- Surface and Thin Film Phenomena
- Advanced Electrical Measurement Techniques
- Magnetic Field Sensors Techniques
- Sensor Technology and Measurement Systems
- Graphene research and applications
- Electrical and Bioimpedance Tomography
- Nanowire Synthesis and Applications
- Silicon Nanostructures and Photoluminescence
- COVID-19 diagnosis using AI
- Neural Networks and Applications
- Power Quality and Harmonics
- Cerebral Palsy and Movement Disorders
- Molecular Junctions and Nanostructures
- Muscle activation and electromyography studies
- Magneto-Optical Properties and Applications
- Geophysical and Geoelectrical Methods
- Maritime Navigation and Safety
- Balance, Gait, and Falls Prevention
- Semiconductor materials and interfaces
- Quantum Dots Synthesis And Properties
- Thin-Film Transistor Technologies
- Diamond and Carbon-based Materials Research
- Semiconductor Quantum Structures and Devices
- Analog and Mixed-Signal Circuit Design
Physikalisch-Technische Bundesanstalt
2020-2025
Stevens Institute of Technology
2020
Fudan University
2017
State Key Laboratory of Surface Physics
2017
Collaborative Innovation Center of Advanced Microstructures
2017
Shanghai University
2013
For more than three decades, GaAs/AlGaAs quantum Hall (QH) devices are being used as standards for the realization of dc resistance unit ohm. Recently, outstanding performance graphene-based (QHR) signifies an immense potential a transition from GaAs to in field and also impedance metrology, with equally good accuracy. The recent developments epitaxial graphene (EG) quality fabrication EG-based doped QHR their improved tested several national metrology institutes (NMIs) all over world have...
Abstract Interlaboratory comparisons of the quantized Hall resistance (QHR) are essential to verify international coherence primary impedance standards. Here, we report on investigation stability p-doped graphene-based QHR devices at direct and alternating currents CMI, KRISS, PTB. To improve electronic transport properties polymer-encapsulated devices, they were shipped in an over-pressurized chamber. The agreement with R K /2 current was order 1 nΩ Ω −1 between 3.5 7.5 T a temperature 4.2...
Biofeedback systems have been extensively used in walking exercises for gait improvement. Past research has focused on modulating the wearer’s cadence, variability, or symmetry, but none of previous works addressed problem inducing a desired speed wearer. In this paper, we present new, minimally obtrusive wearable biofeedback system (WBS) that uses closed-loop vibrotactile control to elicit changes speed, based predicted user response anticipatory and delayed feedback. The performance...
Abstract This paper describes an onsite comparison of two different digital impedance bridges when performing measurements on a quantum Hall resistance standard with the purpose realizing SI unit capacitance, farad. In EMPIR Joint Research Project 18SIB07 GIQS, graphene standards , Physikalisch-Technische Bundesanstalt (PTB), Germany, developed Josephson bridge, and Istituto Nazionale di Ricerca Metrologica (INRIM) Politecnico Torino (POLITO), Italy, electronic bridge. The former is based...
Abstract The outstanding properties and the potential for large‐scale fabrication open a wide field electronic applications of epitaxial graphene on silicon carbide substrates. However, reliable doping methods to permanently control tailor carrier concentration desired value without applying an electrostatic gate are challenging still under investigation. In this study, post‐growth molecular technique is investigated that compensates high electron density pristine by using acceptor F4‐TCNQ....
High-quality Ge nanostructures are obtained by molecular beam epitaxy of on Si(001) substrates at 200 °C and ex situ annealing 400 °C. Their structural properties comprehensively characterized atomic force microscopy, transmission electron microscopy Raman spectroscopy. It is disclosed that they almost defect free except for some defects the Ge/Si interface in subsequent Si capping layer. The misfit strain nanostructure substantially relaxed. Dramatically strong photoluminescence (PL) from...
Photoluminescence (PL) from Si and SiGe is comprehensively modified by Au NPs under excitation without surface plasmon resonance. Moreover, the PL sensitively depends on size of NPs, power thickness layer between SiGe. A model proposed in terms electrostatic effects naturally charged electron transfer through nanoscale metal/semiconductor Schottky junction an external bias or injection carriers. The accounts well for all unique features. It also reveals that can substantially modify energy...
Four optimization deployment performance indexes have been proposed for the problem of multi-sensor platforms in near-space. An adaptive GA algorithm is used to optimize latitude and longitude points' positions Then a linear fitness function constructed based on four indexes. The crossing probability mutation made adapt change values. For appointed ground area, simulations multisensor are carried out values every platform different number calculated. results demonstrate that this paper...
GIQS: Graphene Impedance Quantum Standard is a Joint Research Project of the European Metrology Programme for Innovation and (EMPIR). The project objective to combine novel digital impedance measurement bridges with graphene-based ac quantum Hall resistance standards in simplified cryogenic environment, achieve simple, user-friendly suitable primary realisation units national metrology institutes, calibration centers, industry.
In the last decade, quantum resistance metrology has benefited from application of graphene as base material for fabrication Hall (QH) standards since it allows realization unit ohm in revised International System Units under relaxed experimental conditions. Here, we present a detailed magnetotransport investigation p-type epitaxial graphene, which was doped by molecular acceptor F4-TCNQ. High-accuracy measurements QH show an excellent quantization and reproduction nominal value, half von...
The frequency dependence of the quantized Hall resistance at alternating current results from capacitive losses inside sample as well between and external parts. In this joint effort, we report on ac quantum measurements a graphene-based bar using superconducting contacts novel contact design approach.
In the International System of Units, impedance units can be realized from quantum Hall effect, a macroscopic phenomenon producing quantized resistance values.Established experiments employ individual GaAs devices [1], but novel materials such as graphene exploited to realize with relaxed experimental conditions.Furthermore, simple traceability chains implemented digital bridges.By combining bridges and standards, an easy-to-operate affordable standard has been developed in framework...