The Smallest Stepping Stone: Quantum Dot Physics Using Atomic Defects by Prof Hadar Steinberg
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Join us in the IAS STEM Graduate Colloquium by Prof Hadar Steinberg from the Hebrew University of Jerusalem.
About the talk
Quantum dots (QDs) are conducting regions which can localise few charge carriers, and where the energy spectrum is dominated by Coulomb repulsion. QDs can be as large as few hundreds of nanometers, or as small as a single molecule, their sizes depending on their physical realisation – whether in two-dimensional materials, nanowires, molecular systems.
In my talk I will describe our work on a new type of an atomically-sized QD, realised in defects residing in ultrathin two-dimensional insulators. These defect-dots are found in layered materials such as hexagonal Boron Nitride (hBN), which we study by their assembly into stacked devices. By using graphene electrodes, we are able to electronically couple to the QD, while allowing the QD energy to be externally tuned exploiting the penetration of electric field through graphene.
A consequence of the structure of our devices is that the defect QDs are placed at atomic distance to the conductors on both sides. I will show how the presence of such energy-tunable, atomically sized QDs at nanometer proximity to other conducting systems opens new opportunities for sensitive measurements, including use of QDs as highly sensitive spectrometers, or as single electron transistors, unique in their sensitivity to local electric fields at the nanometer scale. I will discuss our future prospects of using defect QDs as quantum sensors.
About Our Speaker
Hadar Steinberg is a Full Professor working the Racah institute of physics since 2013. His research involves the study of electronic and optical effects in two-dimensional (2D) materials, based on a specialised methods for fabricating intricate electronic devices by assembling layers as thin as a single atom.
Prof Steinberg is interested in a range of topics. These include fundamental problems in superconductivity, such as the role of spins and magnetism in superconducting phases, and the ability to manipulate information at the quantum level. He has spearheaded the development of novel atomic-scale transistors, which can be used as ultra-sensitive local probes, and has developed a new type of sensor for anti-matter particles. His research is funded by competitive grants, including the ERC, ISF, DFG, MOST, the Israeli atomic energy commission, and others.
Since 2023, Prof Steinberg serves as the academic director of the Hebrew University Center for Nano Science and Technology, a research facility of 25 employees. In this role, he oversees the procurement, deployment and management of critical research infrastructure – including electronic microscopes, a range of characterisation and fabrication tools. These are used by over 130 research groups at the university and by high-tech companies across Israel.