Bent Weber

Affiliation: Nanyang Technological University, Singapore

Research Interests: Scanning tunneling microscopy, 2D topological matter, quantum computing, spin qubits

Title: Towards Local EDSR Control of Spin-Defects in 2D Semiconductors

Abstract: Electron and nuclear spins confined to single atoms have become active components in emerging quantum technologies with applications in quantum sensing, computation, simulation, and communication. Most promising are point-defects in semiconductors and insulators, most notably dopants in silicon [1] and colour-centres in diamond [2]. Due to the electrically insulating nature of the crystalline host, spins confined in these systems are often well-isolated from interactions with their environment, allowing for long spin life- and coherence times [3].

Recently, spins confined to atomically-thin (2D) semiconductors with hexagonal lattices [4] have attracted growing attention. This is owing to an inherent coupling of spin and momentum (valley) degrees of freedom in these materials which – in the presence of inversion asymmetry and strong spin-orbit coupling – promises enhanced spin-valley lifetimes (~ seconds) and novel avenues of coherent control by AC electric fields.

In this talk, I will provide an overview of our work on spin-defects in the layered transition metal dichalcogenides (TMDCs) [5-7], investigated in complementary local probe [5] and electron transport [6] spectroscopy. In particular (and in discussion with the audience), we will explore whether atomic spin-defects in the TMDC would owe themselves to coherent control by EDSR – locally via an STM-tip – but within a semiconductor quantum device setting.

[1] He et al., Nature 571, 371 (2019)

[2] Jelezko and Wrachtrup, Phys. Stat. Sol. 203, 3207 (2006)

[3] Steger, Science 336, 1280 (2012)

[4] Liu and Hersam, Nat. Rev. Mater. 4, 669 (2019)

[5] Aliyar, …, and BW, Nano Letters 24, 2142 (2024)

[6] Krishnan, …, and BW, Nano Letters 23, 6171 (2023)

[7] Singh et al. in preparation