Optomechanical effects of two-level systems in a back-action evading measurement of micro-mechanical motion

Journal Article · Mon Jul 29 00:00:00 EDT 2013 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4816428· OSTI ID:22218123

Suh, J.; Weinstein, A. J.; Schwab, K. C. ^[1]

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1. Applied Physics, California Institute of Technology, Pasadena, California 91125 (United States)

We show that the two-level systems (TLS) in lithographic superconducting circuits act as a power-dependent dielectric leading to non-linear responses in a parametrically coupled electromechanical system. Driven TLS shift the microwave resonance frequency and modulate the mechanical resonance through the optical spring effect. By pumping with two tones in a back-action evading measurement, these effects produce a mechanical parametric instability which limits single quadrature imprecision to 1.4 x{sub zp}. The microwave resonator noise is also consistent to a TLS-noise model. These observations suggest design strategies for minimizing TLS effects to improve ground-state cooling and quantum non-demolition measurements of motion.

• OSTI ID: 22218123
• Journal Information: Applied Physics Letters, Vol. 103, Issue 5; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
DEMOLITION
DESIGN
DIELECTRIC MATERIALS
GROUND STATES
MICROWAVE RADIATION
NOISE
OPTICAL PUMPING
PARAMETRIC INSTABILITIES
RESONANCE
SUPERCONDUCTING CAVITY RESONATORS