DIPC Community Seminars: Spins on surfaces for quantum technology
DIPC Seminars
- Speaker
-
Deung-Jang Choi, DIPC
- When
-
2022/05/26
14:00 - Place
- Donostia International Physics Center
- Add to calendar
- iCal
**DIPC Community Seminars**
I will talk about our studies of the properties of magnetic adsorbates as
quantum sensors and as building blocks for quantum information. For my talk, I
have chosen three topics to show our research activities:
1\. Molecules as building blocks for quantum information. Building arrays of
spins is of great interest because of their inherent quantum properties.
Manipulation and transportation of information have been suggested for these
low-dimensional systems [1]. Molecules have unique properties that make them
very interesting for creating low- dimensional systems. In our studies, we
have focused on molecules which have an enormous conductance change. The bias
where the conductance change takes place is determined by the magnetic
anisotropy of the molecule. By following the variations of bias, we can
obtained pertinent information on how the molecules arrange on the surface. We
have shown that using a superconducting STM tip, we can have unprecedented
insight in the molecular array [2].
2\. Electron spin resonance (ESR) with the STM. We have been working in
unravelling the physics under atomic anisotropic gyromagnetic factors [3].
This is of fundamental interest for understanding entanglement between
adsorbed atoms and the possibility of producing quantum operations.
3\. Topological quantum computation (TQC) with the STM. TQC can be studied
using dynamical manipulation of Majoranas with an STM [1]. This is certainly a
very controversial topic despite the large investments made by the information
giants (Microsoft, Google, etc). A candidate for Majoranas is the edge state
produced at the border of spin chains on an s-wave superconductor. In this
context, we have achieved recent evidence that Majoranas may indeed be found
[4].
These three topics are examples of the quantum properties of adsorbates and
how they can be revealed and acted upon. Indeed, in the group of quantum
phenomena on surfaces (https://www.quantumsurface.tk), we are devoted to
showing the extraordinary advantages of the STM as a unique tool that can
explore and give access to quantum technologies.
References:
[1] Colloquium: Atomic spin chains on surfaces. Review of Modern Physics 91,
041001 (2019).
[2] Superconducting scanning tunneling microscope tip to reveal sub-
millielectronvolt magnetic energy variations on surfaces. J. Phys. Chem.
Letters 12, 2983 (2021).
[3] Spin resonance amplitude and frequency of a single atom on a surface in a
vector magnetic field. Phys. Rev. B 104, 174408 (2021).
[4] Atomic manipulation of in-gap states in the Bi2Pd superconductor. Phys.
Rev. B 104, 045406 (2021).
ZOOM: