Journal Article

Strain Tuning of Individual Atomic Tunneling Systems Detected by a Superconducting Qubit

Ustinov, Alexey V., Weiss, Georg, Grabovskij, Grigorij J., Peichl, Torben, Lisenfeld, Jürgen

2012

Overview

In structurally disordered solids, some atoms or small groups of atoms are able to quantum mechanically tunnel between two nearly equivalent sites. These atomic tunneling systems have been identified as the cause of various low-temperature anomalies of bulk glasses and as a source of decoherence of superconducting qubits where they are sparsely present in the disordered oxide barrier of Josephson junctions. We demonstrated experimentally that minute deformation of the oxide barrier changes the energies of the atomic tunneling systems, and we measured these changes by microwave spectroscopy of the superconducting qubit through coherent interactions between these two quantum systems. By measuring the dependence of the energy splitting of atomic tunneling states on external strain, we verify a central hypothesis of the two-level tunneling model for disordered solids.

• Publisher: American Association for the Advancement of Science,The American Association for the Advancement of Science
• Subject: Atoms / Atoms & subatomic particles / Classical and quantum physics: mechanics and fields / Condensed matter: electronic structure, electrical, magnetic, and optical properties / Crystals / Deviation / Electric potential / Energy / Exact sciences and technology / Josephson effect / Low energy / Low temperature / Mathematical models / mechanical stress / Microwaves / Physics / Proximity effects, weak links, tunneling phenomena, and josephson effects, adreev effect, sn and sns junctions / Quantum information / Quantum physics / Quantum tunneling / Qubits (quantum computing) / Railroad grade crossings / Solids / Spectroscopy / Spectrum analysis / Splitting / Strain / Structural strain / Superconductivity / temperature / Tuning / Tunnels