Presentation Information
[3B01]Observation of a Zero-Bias Peak Triggered by a Spin-1/2 Molecule on MgO/Fe(001)
*Toyokazu Yamada1, Kyosei Ishii1, Nana Nazriq1, Peter Krueger1 (1. Graduate School of Engineering, Chiba University)
Developing methods to stabilize isolated spin states on solid surfaces via epitaxial 2D films is crucial for spin-based technologies such as qubits, quantum sensors, and single-atom catalysts. A key step is achieving electronic spin isolation to prolong lifetime and enhance stability. Here, we demonstrate isolated spins on an atomically flat ~1 nm MgO film grown on an oxygen-precoated ferromagnetic Fe(001) whisker [Applied Surface Science 618, 156628 (2023)], using copper phthalocyanine (CuPc, S = 1/2) as a model. The MgO layer electronically decouples CuPc from the substrate, forming a clear HOMO-LUMO gap. Notably, a zero-bias peak (ZBP) appears within this gap, despite the electron-deficient surface near the Fermi level [Ishii et al., Nanoscale Horizons (2025)], suggesting an indirect coupling between the Cu spin and Fe electrons via the MgO valence band and CuPc ligand. The ZBP also extends laterally across the MgO surface. Given that MgO/Fe(001) is widely used in tunnel magnetoresistance devices, these results highlight its potential for engineering isolated spins in quantum applications.