DQMP Forum - Correlated Oxides for Neuromorphic Computing - Laser-based µ-ARPES study of exfoliated few layer Black Phosphorus crystals

19.05.2020 13:00 – 14:30

Correlated Oxides for Neuromorphic Computing
Javier Del Valle Granda (group of Prof. Triscone)

Neuromorphic computing, which mimics the architecture and components of biological neural networks, is an emerging technology which might overcome some of the challenges that traditional computing is facing. A neuromorphic computer is composed of two basic elements: neurons and synapses.
I will show how resistive switching can be used to mimic the functionalities of these two elements, focusing on volatile switching caused by the voltage-triggered insulator to metal transition in VO2 and V2O3. I will discuss several aspects of this transition, such as the underlying mechanism, the dynamics and its spatial distribution. I will also show some of our recent efforts towards emulating neuronal behaviour using this phenomenology.



Laser-based µ-ARPES study of exfoliated few layer Black Phosphorus crystals
Florian Margot (group of Prof. Baumberger)

The optical and transport properties of BP are known to be highly anisotropic and thickness dependent. Together with the high mobility predicted in few layer BP, those properties have sparked the attention of the 2D materials community. Yet, despite intense research, very little is known about the momentum resolved electronic structure in the vicinity of the conduction and valence band edges of thin BP crystals. Building on recent advances, we have been able to perform the first angle resolved photoemission spectroscopy (ARPES) measurements of ultrathin exfoliated BP crystals, ranging from 1 layer to ∼ 8 layers. Our measurements unveil the quantum well structure of electronic states in few layer BP and allow us to determine directly the effective mass and its in-plane anisotropy. A comparison of the measured QP band structure with a tight-binding model for free standing BP suggests a significant modification of the electronic structure by the graphene encapsulation of our samples. We finally discuss spectroscopic signatures of electron-phonon coupling in our data.

Lieu

Zoom Meeting

Please join us on Zoom, Meeting ID: 582 067 708
https://unige.zoom.us/j/582067708

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