Dimensional control of tunneling two level systems in nanoelectromechanical resonators

Abstract

Tunneling two level systems affect damping, noise and decoherence in a wide range of devices, including nanoelectromechanical resonators, optomechanical systems, and qubits. Theoretically this interaction is usually described within the tunneling state model. The dimensions of such devices are often small compared to the relevant phonon wavelengths at low temperatures, and extensions of the theoretical description to reduced dimensions have been proposed, but lack conclusive experimental verification. We have measured the intrinsic damping and the frequency shift in magnetomotively driven aluminum nanoelectromechanical resonators of various sizes at millikelvin temperatures. We find good agreement of the experimental results with a model where the tunneling two level systems couple to flexural phonons that are restricted to one or two dimensions by geometry of the device. This model can thus be used as an aid when optimizing the geometrical parameters of devices affected by tunneling two level systems.

arXiv comment10 pages, 5 figures

References in corpus (24)

• Single-Crystal Diamond Nanomechanical Resonators with Quality Factors exceeding one Million
• Phononic bandgap nano-acoustic cavity with ultralong phonon lifetime
• Quartz Tuning Fork: Thermometer, Pressure- and Viscometer for Helium Liquids
• Surface dissipation in nanoelectromechanical systems: Unified description with the standard tunneling model and effects of metallic electrodes
• Quantum Friction in Nanomechanical Oscillators at Millikelvin Temperatures
• Dissipation due to tunneling two-level systems in gold nanomechanical resonators
• Damping in high-frequency metallic nanomechanical resonators
• Strong gate coupling of high-Q nanomechanical resonators
• Loss channels affecting lithium niobate phononic crystal resonators at cryogenic temperature
• Suspending superconducting qubits by silicon micromachining
• Two-Level System Damping in a Quasi-One-Dimensional Optomechanical Resonator
• Signatures of two-level defects in the temperature-dependent damping of nanomechanical silicon nitride resonators
• Addressing geometric non-linearities with cantilever MEMS: beyond the Duffing model
• Interaction of two level systems in amorphous materials with arbitrary phonon fields
• Dimensional transformation of defect-induced noise, dissipation, and nonlinearity
• Evidence for the role of normal-state electrons in nanoelectromechanical damping mechanisms at very low temperatures
• Operating Nanobeams in a Quantum Fluid
• Nanoscale Real-Time Detection of Quantum Vortices at Millikelvin Temperatures
• Probing superfluid ${}^4\mathrm{He}$ with high-frequency nanomechanical resonators down to $\mathrm{mK}$ temperatures
• Probing Bogoliubov quasiparticles in superfluid ${}^3$He with a 'vibrating-wire like' MEMS device
• Nanomechanical resonators for cryogenic research
• Detecting the "phonon wind" in superfluid ${}^4\mathrm{He}$ by a nanomechanical resonator
• Damping in a Superconducting Mechanical Resonator
• Low temperature dissipation scenarios in palladium nano-mechanical resonators

Cited by in corpus (4)

• Mesoscopic physics of nanomechanical systems
• Superfluid ${}^4$He as a rigorous test bench for different damping models in nanoelectromechanical resonators
• Nanomechanical damping via electron-assisted relaxation of two-level systems
• Aluminum goalpost nano-mechanical devices at low temperatures