@Article{PaulaFerrCarvAgui:2015:HiSeNi,
author = "Paula, L. A. N. and Ferreira, Elvis Camilo and Carvalho, N. C. and
Aguiar, Odylio Denys de",
affiliation = "{Instituto Tecnol{\'o}gico de Aeron{\'a}utica (ITA)} and
{Instituto Nacional de Pesquisas Espaciais (INPE)} and {University
of Western Australia} and {Instituto Nacional de Pesquisas
Espaciais (INPE)}",
title = "High sensitivity niobium parametric transducer for the Mario
Schenberg gravitational wave detector",
journal = "Journal of Instrumentation",
year = "2015",
volume = "10",
keywords = "Instrument optimisation, resonant deterctors, modeling of
microwave systems.",
abstract = "Parametric transducers can work below the quantum limit of
sensitivity for resonant mass gravitational wave detectors. This
makes them a promising alternative for electromechanical
transductance for such detectors. These transducers consist of a
reentrant superconducting niobium cavity coupled to a mass-spring
system with three mechanical modes. These cavities have a central
post responsible for creating a narrow axial gap between its top
and the cavity wall, which is a resonant membrane. Their
displacement sensitivity (df/dx) increases as the gap spacing
decreases. However, this is not a linear relationship and the
dimensioning of the cavity becomes critical if the gap is of the
order of a few microns. In this paper, we describe how to obtain a
gap spacing of ~ 3 \μ m and also the development of
parametric transducers that will be employed in the coming
experimental runs of the Schenberg gravitational wave antenna.
Mechanical thinning methods were performed followed by mechanical
and electrical frequency measurements to tune the device to
operate at the required frequencies. The main results present
better frequency stability and an improvement of df/dx by one
order of magnitude higher than the preceding models. These results
will allow us to reach the quantum limit of detector sensitivity
of ~ 10\−22 Hz\−1/2 in the near future, making it
possible to search for gravitational waves around 3.2 kHz.",
doi = "10.1088/1748-0221/10/03/P03001",
url = "http://dx.doi.org/10.1088/1748-0221/10/03/P03001",
issn = "1748-0221",
language = "en",
urlaccessdate = "27 abr. 2024"
}