Back to overview

Invited Lecture

Magnetoelectric Composites: from Sensors to Sensor Systems

Wednesday (07.06.2017)
21:40 - 22:20 Förde II + III
Part of:
Line-Up:
12:20 Invited Lecture Similarities and differences between magnetic hysteresis and hysteresis in phase transformations 0 Richard James
13:00 Invited Lecture Discovery and Design of Multifunctional Materials using Combinatorial and High-Throughput Experimentation 1 Prof. Dr. Alfred Ludwig
15:10 Invited Lecture Tuning Mechanical Properties of Spider Cuticle by its Composition and by Structural Gradients 0 Dr. Yael Politi
15:50 Invited Lecture Surfaces and Gels for controlling Calcium Phosphate Deposition 0 Prof. Dr. Andreas Taubert
17:40 Invited Lecture Probing the Structure and Dynamic Behaviors of Ferroelectrics by Electron Microscopy with Atomic Resolution in Real Time 0 Prof. Xiaoqing Pan
18:20 Invited Lecture Magnetoelectric Composites for Energy Harvesting 1 Robert E. Hord, Jr. Professor Shashank Priya
19:40 Invited Lecture Declamping in Lead Magnesium Niobate – Lead Titanate Films 1 Prof. Susan Trolier-McKinstry
20:20 Invited Lecture Integrated Magnetics and Multiferroics for Compact and Power Efficient Sensing, Power, RF, Microwave and mm-Wave Electronics 0 Prof. Nian X. Sun
21:00 Invited Lecture From Maxwell’s displacement current to nanogenerator driven self-powered systems and blue energy 0 Prof. Zhong Lin Wang
21:40 Invited Lecture Magnetoelectric Composites: from Sensors to Sensor Systems 0 Prof. Dr.-Ing. Gerhard Schmidt
22:20 Invited Lecture Metal–insulator transition in vanadium oxides films and its applications 1 Dr. Keisuke Shibuya
00:20 Invited Lecture In operando photoemission spectroscopy of PMN-PT interfaces 0 Prof. Dr. Kai Rossnagel
08:30 Invited Lecture Titanium-Tantalum High Temperature Shape Memory Spring Actuators 1 Prof. Dr. Gunther Eggeler
09:10 Invited Lecture Vortex-antivortex topological structures in multiferroic tunnel junctions 1 Dr. Ana Sanchez
09:50 Invited Lecture Artificial Ferroic Systems 1 Prof. Laura Heyderman
17:40 Invited Lecture Biomimicry at the molecular level: Molecularly imprinted polymers as synthetic antibody mimics 0 Karsten Haupt
Session Chair
Topic Invited Lecture:
Belongs to:


When

measuring small magnetic fields as they appear in medical or biological

applications, both, very small and very large signal amplitudes are observed at

the same time. Small amplitudes stem, e.g., from human sources such as the

human heart (magnetocardiography) or brain (magnetoencephalography). Low

frequency signals (0.5 to 40 Hz) can be measured here with peak amplitudes of

about 100 pT (heart) or even less than 1 pT (brain). Superposed to these small

signals are usually large signal components that stem either from artificial

sources, such as excitation signals utilized for modulation techniques, or from

natural sources such as the magnetic field of the earth. Creating digital

signals that can be used for detailed (medical) analyses is an interesting

challenge for both, material scientists and engineers.


Methods for improving the signal quality (mainly in terms of signal-to-noise

ratio) can be grouped into analog and digital approaches, indicating whether

they are performed prior or after the analog-to-digital (AD) conversion.


If sensors with a limited dynamical range are used in unshielded environments,

additional coils can be used for creating a so-called anti field that cancels

the magnetic field of the earth or other disturbing components. The driving

(analog) currents of such coils can be generated adaptively using (digital)

hardware. In the same manner, operation points can be stabilized. Furthermore,

voltage adders can be used to cancel typical power supply distortions (50 or 60

Hz) or excitation signals that are required for modulation-based sensor

read-out principles.


After the AD conversion so-called reference sensors can be used for recording

signals that show a strong correlation with the disturbing but not with the

desired signal component. Again, adaptive filtering techniques can be used to

enhance the signal quality. However, such approaches are only successful if the

analog amplifier followed by the AD converter are not saturated. Furthermore,

often magnetoelectic sensors can be read out in a multitude of modes. This allows

for adaptive combination of the individual signals, leading to improved

robustness and better signal-to-noise ratio. In addition, several sensors can

be combined and postprocessing such as digital noise suppression can be applied

finally.


As a consequence, more “ingredients” than just the sensor are required for an

entire sensor system. This leads to very interesting multidisciplinary research

approaches. From sensor to sensor systems: it’s a rocky road.

 

Speaker:
Prof. Dr.-Ing. Gerhard Schmidt
Kiel University (CAU)