Joule spectroscopy of hybrid superconductor-semiconductor nanodevices.

Hybrid superconductor-semiconductor devices offer highly tunable platforms, potentially suitable for quantum technology applications, that have been intensively studied in the past decade. Here we establish that measurements of the superconductor-to-normal transition originating from Joule heating provide a powerful spectroscopical tool to characterize such hybrid devices. Concretely, we apply this technique to junctions in full-shell Al-InAs nanowires in the Little-Parks regime and obtain detailed information of each lead independently and in a single measurement, including differences in the superconducting coherence lengths of the leads, inhomogeneous covering of the epitaxial shell, and the inverse superconducting proximity effect; all-in-all constituting a unique fingerprint of each device with applications in the interpretation of low-bias data, the optimization of device geometries, and the uncovering of disorder in these systems. Besides the practical uses, our work also underscores the importance of heating in hybrid devices, an effect that is often overlooked.

Potential pitfalls of initiating a newborn hearing screening program.

OBJECTIVE: To examine the efficacy of a universal screening program for infant hearing. DESIGN: Retrospective analysis. SETTING: Tertiary care center. PATIENTS: We examined 2289 (90.2%) of 2537 infants born at our institution from April 1, 1995, to June 30, 1996, for hearing loss (HL). INTERVENTIONS: We used a 3-stage protocol with transient evoked otoacoustic emissions (TEOAE) in stages 1 and 2 and diagnostic evaluation in stage 3. Infants without reproducible TEOAEs in either ear after stage 2 were referred to stage 3. MAIN OUTCOME MEASURES: Specificity of TEOAE, incidence of HL, prevalence of risk factors for HL, cost of TEOAE screening, and identification of barriers to universal screening. RESULTS: Of the infants undergoing TEOAE screening, 91.1% passed stage 1. Of infants needing repeated testing, 73.7% passed and 26.2% failed. Of the 43 infants referred for diagnostic evaluation, 5 (11.6%) had HL. The combined incidence of conductive and sensorineural HL was 2.18 per 1000 newborns. The prevalence of at least 1 risk factor for HL was 10.4%. The estimated cost of TEOAE screening was $24.48 per infant. Ten percent of infants did not undergo screening due to program deficiencies. CONCLUSIONS: Screening with TEOAE was sufficiently specific for universal screening. However, we were unable to achieve truly universal screening. This is probably the reason for our lower incidence of sensorineural HL. We were unable to continue our universal newborn screening program, due to lack of funding, difficulties with program implementation, and our low incidence of detected HL.