Speaker
Description
Quantum sensing for particle-physics applications often relies on coherent quantum systems in which weak external perturbations are converted into measurable shifts in transition frequency or accumulated quantum phase1,2. Molecular spin qubits provide a chemically tuneable platform for developing spin-based quantum sensing. In these systems, an applied electric field perturbs the spin Hamiltonian, producing an electric-field-dependent transition frequency, ∆𝜐 = 𝑘𝐸, and hence a measurable phase shift, ∆𝜙 = 2𝜋 ∫ 𝑘𝐸(𝑡)𝑦(𝑡)𝑑𝑡 3. Systems with appreciable spin-orbit coupling and ligand-field interactions are especially promising because these interactions can enhance the coupling between electric-field induced changes in molecular structure and the effective spin Hamiltonian 4.
We use pulsed ESR to primarily investigate the spin–electric field coupling (SEC) of Yb(trensal) diluted in a diamagnetic host5. We compare the dependence of the SEC on the orientation of an applied electric field with respect to the crystal. In contrast to the behaviour expected for a purely axial response4, Yb(trensal) exhibits an SEC even when the electric field is oriented perpendicular to the molecular C3 axis. This is still observed in geometries where the C3 axis is perpendicular to both the electric and magnetic fields, with a magnitude comparative to the axial response. In addition, we also look at the effects of adding the methoxy group in the ortho and para positions to the phenoxide group, exploring the Yb(trenovan) and Yb(trenpvan) compounds respectively6.