Clock Transitions Generated by Defects in Silica Glass

Abstract

Clock transitions (CTs) in spin systems, which occur at avoided level crossings, enhance quantum coherence lifetimes T${}_2$ because the transition becomes immune to the decohering effects of magnetic field fluctuations to first order. We present the first electron-spin resonance (ESR) characterization of CTs in certain defect-rich silica glasses, noting coherence times up to 16 $\mu$s at the CTs. We find CT behavior at zero magnetic field in borosilicate and aluminosilicate glasses, but not in a variety of silica glasses lacking boron or aluminum. Annealing reduces or eliminates the zero-field signal. Since boron and aluminum have the same valence and are acceptors when substituted for silicon, we suggest the observed CT behavior could be generated by a spin-1 boron vacancy center within the borosilicate glass, and similarly, an aluminum-vacancy center in the aluminosilicate glass.

The Main Manuscript features 9 pages, 5 figures, and 1 table. The Supplement features an additional 6 pages, 4 figures, and two tables

References in corpus (19)

• Quantum Computing in Molecular Magnets
• Superconducting Qubits: Current State of Play
• Trapped-Ion Quantum Computing: Progress and Challenges
• Hybrid Quantum Processors: molecular ensembles as quantum memory for solid state circuits
• Hybrid quantum circuit with a superconducting qubit coupled to a spin ensemble
• Magnetic qubits as hardware for quantum computers
• Atomic clock transitions in silicon-based spin qubits
• Decoherence in Crystals of Quantum Molecular Magnets
• Quantum-Coherent Nanoscience
• Single-molecule Nanomagnets
• Hybrid solid state qubits: the powerful role of electron spins
• Enhanced molecular spin-photon coupling at superconducting nanoconstrictions
• Storing quantum information in spins and high-sensitivity ESR
• Broadband loop gap resonator for nitrogen vacancy centers in diamond
• Multimode storage of quantum microwave fields in electron spins over 100 ms
• A Clock Transition in the Cr${}_7$Mn Molecular Nanomagnet
• Constructing Clock-Transition-Based Two-Qubit Gates from Dimers of Molecular Nanomagnets
• Adjustable coupling and in-situ variable frequency EPR probe with loop-gap resonators for spectroscopy up to X-band
• Revealing the Intrinsic Magnetism of Non-Magnetic Glasses

Cited by in corpus (1)

• Enhancing Coherence with a Clock Transition and Dynamical Decoupling in the Cr${}_7$Mn Molecular Nanomagnet