Magnetostriction measurements at milli-kelvin temperatures using a Fabry-Pérot interferometer.

This paper demonstrates an optical technique to measure magnetostrictive strain in a cryogenic environment using a Fabry-Pérot resonator spaced by crystal samples. Optical measurement techniques are calibration-free and highly sensitive. This technique was used to measure the magnetostrictive strain of neodymium gallate at a temperature of 49 mK to be λ = 1.

Visualising the heart of chaos.

The intra-cavity electro-magnetic field distribution in a microdisk resonator can be visualised by inducing a phase shift via a scanning probe beam.

Dielectric perturbations: anomalous resonance frequency shifts in optical resonators.

Small perturbations in the dielectric environment around resonant dielectric structures usually lead to a frequency shift of the resonator modes directly proportional to the polarizability of the perturbation. Here, we report experimental observations of strong frequency shifts that can oppose and even exceed the contribution of the perturbations' polarizability. We show in particular how the mode frequencies of a lithium niobate whispering-gallery-mode resonator are shifted by planar substrates-of refractive indices ranging from 1.

Unexpected tunnelled central venous access demise: a single institutional study from the UK.

Purpose: To explore the factors involved in the demise of tunnelled central vascular access devices (CVADs) in children and describe patterns of failure.

Methods: A retrospective study including children under 16 years of age undergoing CVAD insertion in a tertiary centre between October 2014 and December 2019. The Kaplan-Meier estimator was used to study CVAD survival and piecewise exponential curves to approximate hazard rates.

A charge parity ammeter.

A metallic double dot is measured with radio frequency reflectometry. Changes in the total electron number of the double dot are determined via single electron tunnelling contributions to the complex electrical impedance. Electron counting experiments are performed by monitoring the impedance, demonstrating operation of a single electron ammeter without the need for external charge detection.