Efrem Ejigu
| Accurate
clinical
tympanic
measureme
nt system at
the NMISA,
NCSLI
measure
| Infrared ear thermometers allow users to measure body temperature
quickly and non-invasively by inserting a probe into the patient’s ear
canal. The effectiveness of tympanic ear thermometers is dependent on
how accurate their measurement is. This prompts the demand for
accurate and reliable calibration of ear thermometers. Developing
capability and providing traceability to the health care facilities in South
Africa have become crucial, as there is no calibration laboratory that
provides such a service. A standard ear-thermometer black-body source
system that is traceable to ITS-90 temperature has been constructed and
assembled at the NMISA temperature laboratory. The ITS-90-traceable
measurement system developed has a measuring capability of 40 mK
(k=2) to 70 mK (k=2) in the temperature range of 35.5 °C to 41.5 °C. At
the human body temperature of 37 °C an uncertainty of 45 mK (k=2) is
| Journal of
Measurement
Science
|
|
Dr Angelique
Botha
| The
standard of
standardsetting
| Standards developed by the International Organisation for
Standardisation are often hidden in plain sight. ISO 6 is a standard for
camera film speeds that was developed to allow photographers to select
the right film for their purpose, considering factors such as the available
levels of lighting and the speed of their subject. In sunny weather, a
slower film with a low ISO number, such as ISO 100 worked best,
whereas a faster, more reactive film was required for cloudier conditions.
Even today, you will still find an ISO setting on your digital camera. The
linked article below will tell you more about the history and work of ISO
and some of the other interesting standards that the organisation has
developed.
| Measure for
measure
| Click to open
|
Filippus S.
Roux
| Stimulated
parametric
downconversionion
for
spatiotemporal metrology
| The process of the stimulated parametric down-conversion is analyzed
with the aid of a Wigner functional approach to investigate the effects of
the spatiotemporal degrees of freedom. The output state from this process is represented by a Bogoliubov transformation of the input state,
where the Bogoliubov coefficients become kernel functions representing
the spatiotemporal properties of the process in the full Wigner functional
approach. It thus reveals the effect of the experimental parameters in
such a process which are important in metrology applications, such as
nonlinear interferometry
| Physical Review
| Click to open
|
Filippus S.
Roux
| Spatiotemp
oral effects
on
squeezing
measureme
nts
| Squeezed photonic states that are produced by parametric downconversion are investigated with the aid of a functional approach to reveal
the effect of the spatiotemporal degrees of freedom, in terms of the
experimental conditions for the preparation of such states and the
homodyne measurements with which the amount of squeezing is
determined. The analysis reveals that the squeezed state loses its
minimum uncertainty property when the efficiency of the down-conversion
process is increased, depending on the experimental conditions of the
homodyne measurement.
| Physical review
| Click to open
|
Filippus S.
Roux
| Spatiotemp
oral effects
on
squeezing
measurements
| Computational techniques, based on the use of generating functions are presented to alleviate calculations that are required to identify nonclassical properties of quantum. These techniques use the Wigner functions of these quantum states. Example of quantum states with nonclassical properties are those from which a certain number of photons are removed. Here, both the formal definition of such photon-subtracted states in terms of ladder operators and the experimental implementation with heralded photon detections are considered. These techniques are demonstrated with photon subtraction from squeezed thermal states as well as squeezed Fock states
| Journal of Optics
| Click to open
|
Filippus S.
Roux
| Toolbox for
nonclassical
state
calculations
| Computational techniques, based on the use of generating functions are
presented to alleviate calculations that are required to identify nonclassical properties of quantum. These techniques use the Wigner
functions of these quantum states. Example of quantum states with nonclassical properties are those from which a certain number of photons are
removed. Here, both the formal definition of such photon-subtracted
states in terms of ladder operators and the experimental implementation
with heralded photon detections are considered. These techniques are
demonstrated with photon subtraction from squeezed thermal states as
well as squeezed Fock states
| Journal of
Optics
| Click to open
|
Andrew
Forbes,
Francesco
Petruccione,
and Filippus
S. Roux3
| Toward a
quantum
future for
South Africa
| Here, the authors report on the formation of the South African Quantum
Technologies Initiative (SA QuTI), which was formally launched by the
South African Department of Science and Innovation (DSI) with the first
seed funding released in September 2021. They share their perspectives
on what this means for South Africa’s quantum future.
| AVS Quantum
Science
| Click to open
|
Nompumelelo
Leshabane,
James
Tshilongo,
Shadung J.
Moja, Napo
G. Ntsasa,
Gumani
Mphaphuli &
Mudalo I.
Jozela
| Quantitation
of hydrogen
sulphide
reference
gas
mixtures to
provide
traceability
for indoor
air quality
monitoring
| The peer-reviewed publication was achieved through the improvement
work done for hydrogen sulphide measurements in South Africa.
Measurement of hydrogen sulphide (H2S) has increased over the past
years, with more and more industries measuring H2S since it has been
identified as a key pollutant currently being measured to comply with
legislation on indoor air quality. The research objectives investigated and
reported on different techniques used for quantification of hydrogen
sulphide gas mixtures. Following improved methodology, accuracy and
overall measurement uncertainties for H2S gas mixtures produced at
NMISA has improved. With the research work reported in the publication,
the laboratory has improved H2S national measurement standards which
is disseminated to the indoor air quality monitoring industry through the
provision of primary reference gas mixtures. This contributes to an
improved quality of life for South African citizens and enables compliance to legislation and ensures that reliable emission measurements are
reported through the provision of reliable primary reference gas mixtures.
| Accreditation
and Quality
Assurance
(ACQUAL)
Journal
| Click to open
|
Valeria RodríguezFajardo, Carmelo
RosalesGuzmán,
Othmane
Mouane,
Daniel
Wamwangi,
Elias
SiderasHaddad,
Filippus S.
Roux &
Andrew
Forbes
| All-digital
3-dimension
al
profilometry
of
nano-scaled
surfaces
with spatial
light
modulators
| In this work, a contactless, non-destructive, fast surface metrology
method is proposed in which a common-path interferometer and a liquid
crystal spatial light modulator is used to scan the sample and introduce
phase delays, making the system completely digital. It demonstrates good
correlations between the measured and reference surfaces sharp
changes in height. This method is expected to be of interest to the optical
metrology community for applications in surface profilometry.
| Applied Physics
| Click to open
|
