skip to main content

SciTech ConnectSciTech Connect

Title: Quantum point contact displacement transducer for a mechanical resonator at sub-Kelvin temperatures

Highly sensitive displacement transduction of a 1.67 MHz mechanical resonator with a quantum point contact (QPC) formed in a GaAs heterostructure is demonstrated. By positioning the QPC at the point of maximum mechanical strain on the resonator and operating at 80 mK, a displacement responsivity of 3.81 A/m is measured, which represents a two order of magnitude improvement on the previous QPC based devices. By further analyzing the QPC transport characteristics, a sub-Poisson-noise-limited displacement sensitivity of 25 fm/Hz{sup 1/2} is determined which corresponds to a position resolution that is 23 times the standard quantum limit.
Authors:
; ; ; ;  [1]
  1. NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198 (Japan)
Publication Date:
OSTI Identifier:
22224084
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 103; Journal Issue: 19; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ELECTRIC CONTACTS; GALLIUM ARSENIDES; MHZ RANGE 01-100; NOISE; PIEZOELECTRICITY; POSITIONING; RESOLUTION; RESONATORS; SENSITIVITY; STRAINS; TRANSDUCERS