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DOE OSTI · 1905568

Spectral Addressability in a Modular Two Qubit System

von Kugelgen, Stephen·Krzyaniak, Matthew D.·Gu, Mingqiang·Puggioni, Danilo·Rondinelli, James M.·Wasielewski, Michael R.·Freedman, Danna E.
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Abstract

The combination of structural precision and reproducibility of synthetic chemistry is perfectly suited for the creation of chemical qubits, the core units of a quantum information science (QIS) system. By exploiting the atomistic control inherent to synthetic chemistry, we address a fundamental question of how the spin–spin distance between two qubits impacts electronic spin coherence. To achieve this goal, in this study we designed a series of molecules featuring two spectrally distinct qubits, an early transition metal, Ti 3+ , and a late transition metal, Cu 2+ with increasing separation between the two metals. The spectral separation between the two metals enables us to probe each metal individually in the bimetallic species and compare it with monometallic control samples. Coherence times found to be governed by the distance to nuclear spins on the other qubit’s ligand framework. This finding offers guidance for the design of spectrally addressable molecular qubits.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYDiffusionElectron paramagnetic resonance spectroscopyMagnetic propertiesPyrrolesQuantum mechanics

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von Kugelgen, Stephen, Krzyaniak, Matthew D., Gu, Mingqiang, Puggioni, Danilo, Rondinelli, James M., Wasielewski, Michael R., Freedman, Danna E.. 2021-05-20. Spectral Addressability in a Modular Two Qubit System. https://doi.org/10.1021/jacs.1c02417

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