Lehrstuhl für Nanoelektronik

Aktuelles

COLOR LINE WORKSHOP II: NEUROTRONICS, 2. SEPTEMBER BIS 5. SEPTEMBER, CAU KIEL UND COLORLINE FÄHRE KIEL-OSLO-KIEL

15.04.2020

Anfang September 2019 organisierte die Forschungsgruppe 2093 zum zweiten Mal den ColorLine Workshop in Kiel. Der Workshop fand am ersten Tag an der Technischen Fakultät der CAU Kiel statt, bevor es an den darauffolgenden Tagen auf das Fährschiff ColorLine ging, welches täglich zwischen Kiel und Oslo pendelt.
Die zahlreichen Vorträge und Diskussionen wurden in den Konferenzräumen mit Sicht auf die Ostsee fortgesetzt. Hier konnte der Eindruck gewonnen werden, dass sich der gegebene Blick in die Weite auf so mache Forschungsperspektive übertrug.
Wie schon beim ersten Mal nahmen wieder ca. 40 Forscher an dieser Veranstaltung in Kiel teil. Der Workshop ist Teil der internationalen Aktivitäten im Rahmen der Forschungsgruppe 2093 und reflektiert ihren interdisziplinären Charakter.
Auch diesmal konnten elf international angesehene Referenten aus den Bereichen Memristives Devices, Advanced Synchrotoron Analytics, Neuro-Biology und Graph Theory für die Teilnahme am ColorLine Workshop gewonnen werden.

André Fiala (Department of Molecular Neurobiology of Behavior, Georg-August-University of Göttingen)
Mark Shein-Idelson (Department of neurobiology and the Sagol School for Neuroscience, Tel-Aviv University, Israel)
Simon Rumpel (Institute of Physiology, Focus Program Translational Neurosciences, University Medical Center, Johannes Gutenberg University Mainz)
Philipp Hoevel (School of Mathematical Sciences, University College Cork, Ireland)
Claus C Hilgetag (Institute of Computational Neuroscience, University Medical Ctr Eppendorf, Hamburg University)
Bernabé Linares-Barranco (Instituto de Microelectrónica de Sevilla (IMSE-CNM), CSIC and Universidad de Sevilla)
Paolo Milani (CIMAINA and Department of Physics, University of Milano, Italy)
Beatriz Noheda (Zernike Institute for Advanced Materials & Groningen Cognitive Systems and Materials center (CogniGron) University of Groningen, The Netherlands)
Christoph Schlueter (Photon Science, Deutsches Elektronen-Synchrotron DESY, Hamburg)
Yury Matveyev (Deutsches Elektronen-Synchrotron DESY, Hamburg)
Bruno Barazani (Interdisciplinary Institute for Technological Innovation - 3IT, University of Sherbrooke, Quebec, Canada)

Programm

 

Wie analog wird Industrie 5.0?

08.08.2018

Am 31.05.2018 veranstaltete die Staatskanzlei von Schleswig-Holstein mit opencampus.sh, der DiWiSH und der Fachhochschule Kiel – ein Netzwerktreffen zur künstlichen Intelligenz (KI).
Landesregierung Presse
In einer Reihe von Kurzbeiträgen gingen Referenten aus der Industrie, Selbständige sowie Vertreter aus Schulen und Hochschulen auf die Chancen und Risiken der KI ein. Der Beitrag des Lehrstuhls für Nanoelektronik behandelte den oftmals übersehenen Zusammenhang zwischen Information und Energie. Extrapoliert man die derzeitige Entwicklung im Bereich KI, so wird in der Mitte des 21. Jahrhunderts die gesamte erzeugte elektrische Energie für die Informationstechnologie benötigt. Welche zukünftige Technologie einen Ausweg bahnen könnte, ist in dem mitgeschnitten Beitrag zu sehen:

https://vod.oksh.de/media/1527846493/main.mp4
 

Dr. habil. Martin Ziegler vom Lehrstuhl für Nanoelektronik nimmt einen Ruf auf eine W3-Professur an der TU Ilmenau an

08.06.2018

Dr. habil. Martin Ziegler vom Lehrstuhl für Nanoelektronik von der Technischen Fakultät der CAU Kiel hat einen Ruf von der TU Ilmenau auf eine W3 Professur mit dem Titel „Mikro und nanoelektronische Systeme“ erhalten und kürzlich angenommen. Dr. Martin Ziegler wird seine Professur zum 01. Juli 2018 an der TU Ilmenau antreten. Seine Kollegen am Institut für Elektrotechnik und Informationstechnologie und vom Institut für Materialwissenschaften gratulieren ihm zu diesem großartigen Erfolg. Obgleich Herr Dr. Martin Ziegler die CAU Kiel verlassen wird, so wird er seine erfolgreiche Forschungstätigkeit innerhalb der DFG Forschergruppe 2093 mit dem Titel „Memristive Bauelemente für neuronale Systeme“ fortsetzen. Darüber hinaus ist geplant die Kooperation zwischen der TU Ilmenau und der CAU Kiel weiter zu vertiefen und auszubauen.

Memristive device based on a depletion-type SONOS field effect transistor

07.06.2017

State-of-the-art SONOS (silicon-oxide-nitride-oxide-polysilicon) field effect transistors were operated in a memristive switching mode. The circuit design is a variation of the MemFlash concept and the particular properties of depletion type SONOS-transistors were taken into account. The transistor was externally wired with a resistively shunted pn-diode. The underlying memristive mechanism is purely electronic, which eliminates an initial forming step of the as-fabricated cells. This fact, together with reasonable design flexibility, in particular to adjust the maximum RON/ROFF ratio, makes these cells attractive for neuromorphic applications.
 

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In situ hard x-ray photoemission spectroscopy of barrier-height control at metal/PMN-PT interfaces

07.07.2016

With an ever-decreasing device sizes, it becomes fundamental to investigate the interfaces thoroughly in order to understand fully and manipulate the device functionalities. Here, we report the structural and electronic properties of metal/ferroelectric, Au(SRO)/PMN-PT, interfaces under in-situ bias voltage using hard x-ray photoelectron spectroscopy (HAXPES). The paper is highlighted as an editors`suggestion in Physical Review B.

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Polarity-tunable spin transport in all-oxide multiferroic tunnel junctions

26.05.2016

Multiferroic tunnel junctions (MFTJs) are the next generation non-volatile memory devices that offer multinary memory states in response to electric- and magnetic-fields, referring to tunneling electroresistance (TER) and tunneling magnetoresistance (TMR), respectively. In the article recently published in Nanoscale, our results on nominally symmetric epitaxial LSMO/PZT/LSMO MFTJs revealed that the inherent asymmetry in the MFTJ (arising from the microstructural and chemical asymmetry at the interfaces) likely suffices to drive the intertwined TER and TMR.

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Pattern recognition with TiOx-based memristive devices

10.08.2015

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 In a recent publication the development of TiO2-x-based memristive devices for bio-inspired neuromorphic systems is reported. A physical-based equivalent circuit model is employed to analyze the obtained switching characteristics in some more detail and to provide a realistic device model for network level simulations. As an example for a neural network application of the developed devices, a pattern recognition system was investigated by using the well accepted MNIST Database benchmark system. The recognition model system compromises memristive devices with gradual (homogenous) I-V characteristics, a cross-bar array with a feed-forward neural network, leaky-integrate-and-fire neurons including a winner-take it all strategy.

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Hebbian plasticity model for memristive devices

07.05.2015

.   In a recent publication we discuss the requirements of individual memristive devices for the emulation of Hebbian plasticity in neuromorphic applications. The paper presents a plasticity model suitable for memristive devices based on advanced novel learning rules, which provide Hebbian plasticity in accordance to the Bienenstock-Cooper-Munro (BCM) rule.

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Observation of 0–π transition in SIsFS Josephson junctions

15.01.2015

The 0-π transition in Superconductor-Insulator-superconductor-Ferromagnet-Superconductor (SIsFS) Josephson junctions (JJs) was investigated experimentally. As predicted by theory, an s-layer inserted into a ferromagnetic SIFS junction can enhance the critical current density up to the value of an SIS tunnel junction. We fabricated Nb'|AlOx|Nb|Ni60Cu40|Nb JJs with wedge-like s (Nb) and F (Ni60Cu40) layers and studied the Josephson effect as a function of the s- and F-layer thickness, ds and dF, respectively. For ds = 11 nm, π-JJs with SIFS-type jc(dF) and critical current densities up to jc = 60 A/cm²  were obtained at 4.2 K. Thicker ds led to a drastic increase of the critical current decay length, accompanied by the unexpected disappearance of the 0-π transition dip in the jc(dF) dependence. Our results are relevant for superconducting memories, rapid single flux quantum logic circuits and solid state qubits.

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Giant electrode effect on tunnelling electroresistance in ferroelectric tunnel junctions

24.12.2014

In recent years, tunneling electroresistance effect in ferroelectric tunnel junctions (FTJs) has evoked great interest within the scientific community as a potential candidate for future non-volatile memory, logic and neuromorphic computing applications.

In the article recently published in Nature Communications, we study theoretically and experimentally the ferroelectric/metal electrode interface role in determining the ferroelectric driven tunneling electroresistance (TER) effect. We believe our findings would impact significantly on optimization of FTJs in terms of electrode materials design.

Reference:  Rohit Soni, Adrian Petraru, Paul Meuffels, Ondrej Vavra, Martin Ziegler, Seong Keun Kim,
Doo Seok Jeong, Nikolay A. Pertsev & Hermann Kohlstedt, Giant electrode effect on tunnelling electroresistance in ferroelectric tunnel junctions. Nat. Commun. 5:5414 doi: 10.1038/ncomms6414 (2014).

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Strain effects on the transition temperature in vanadium dioxide thin films

05.11.2014

The metal–insulator transition (MIT) in VO2 is accompanied by an abrupt change in the conductivity and optical properties, raising a large interest for theoretical studies as well for potential application in sensing and switching.

Controlling the transition temperature of these materials in a wide range is of particularly high interest. This can be achieved by doping or by strain in thin films.
We investigate the effect of strain in epitaxially grown vanadium dioxide films on various crystalline substrates. Moreover, by growing these films on piezoelectric substrates with huge piezoelectric coefficients like PMN-PT, we are able control the strain in a continuous way by simply applying an external bias to the substrate.

Electrostatic surface charge, photon irradiation or current excitation are recently investigated as key parameters for external control of the metal - insulator transition.

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Binary thin films with thickness and composition gradients

03.09.2014

We present a versatile sputter deposition technique to produce alloy layer libraries. Colloidal particles embedded in a matrix can serve as active layers for various structures e.g. in the fields of superconducting electronics and resistive switching. The free choice of materials and the controlled deposition with layer gradients of thickness and composition over the wafer facilitates systematic investigations.

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Visiting scientist in our group

03.09.2014

Dr. Ing. Doo Seok Jeong
Korea Institute of Science and Technology (KIST)

Doo Seok received his BSc and MSc in materials science from Seoul National University in 2002 and 2005, respectively. He received his PhD degree in materials science from RWTH Aachen University, Germany, in 2008. Since 2008, he has worked for KIST.

His research interests are developments of artificial synapses and neurons by means of nanoionic systems and understanding of nanoionic behaviour. In the Figure the potentiation behavior of different memresitive devices are shown. [H. Lim et al. Nanotechnology  24, 384005 (2013).]



Strain effects on the transition temperature in vanadium dioxide thin films

03.09.2014

The metal–insulator transition (MIT) in VO2 is accompanied by an abrupt change in the conductivity and optical properties, raising a large interest for theoretical studies as well for potential application in sensing and switching.

Controlling the transition temperature of these materials in a wide range is of particularly high interest. This can be achieved by doping or by strain in thin films.
We investigate the effect of strain in epitaxially grown vanadium oxide films on various crystalline substrates.

Electrostatic surface charge, photon irradiation or current excitation are recently investigated as key parameters for external control the metal - insulator transition.

Taylored pi shifters for RSFQ logic

03.09.2014

Rapid single flux quantum logic (RSFQ) is a superconducting, inherently digital circuit design. The information is represented and transmitted by single flux quanta h/2e (elementary charge e and Planck’s constant h) that are stored in superconducting loops.

Josephson junctions represent the active elements of the circuit. To enhance the robustness and design of the circuit a "complementary" Josephson junction, called Pi Junction, is desireable. They exist but suffer from poor operation parameters. We fabricated Pi junctions that show potential to drastically increase the critical current density of previous concepts.

An electronic implementation of amoeba anticipation is highlighted by Advances in Engineering

03.09.2014

Anticipation in biological systems is the process of speculation of the probable future based on the memory of past events. In nature, anticipation can be already observed in unicellular organisms like amoebas...

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