arXiv subjects

Giada Bucci

Publications and source records attributed to Giada Bucci.

4 recordsLinked to original sources

arXiv2026

Emission dynamics in zincblende InAsxP1-x quantum dots in InP nanowires: influence of quantum dot size, composition and nanowire geometry

Hereby, we present an experimental and theoretical investigation of emission dynamics in zincblende InAsxP1-x quantum dots (QDs) embedded in InP nanowires (NWs) grown via vapour-liquid-solid mechanism by chemical beam epitaxy, using Au nanoparticles as a nucleation catalyst. By measuring time-resolved photoluminescence from an ensemble of QD-NWs it was possible to determine the exciton lifetime dependence on QD composition and height. Changes in the InP shell thickness surrounding the InP NW stem with a QD, brought additional insight into the influence of photonic environment on the carrier dynamics. High-resolution transmission electron microscopy, combined with energy-dispersive X-ray spectroscopy, provided actual structural parameters. The experimentally obtained lifetimes were interpreted in the light of results of 8 band kp calculations combined with configuration-interaction model to take into account the Coulomb interactions and finite-difference time domain photonic simulations to include the effect of optical confinement. The full understanding of the experimental results required considering both, the changes in the QD potential and the Purcell effect, the latter leading to spontaneous emission inhibition in the case of NWs with thin InP shell.

cond-mat.mes-hall↗

arXiv2026

Growth and Transport Properties of InAsSb Nanoflags

The present work reports, for the first time, the growth of high-quality free-standing InAsSb nanoflags and their electronic properties. Different growth conditions have been explored, and zinc-blende InAsSb nanoflags of various composition have been obtained. In particular, InAs0.77Sb0.23 nanoflags are on average (2000+-180) nm long, (640+-50) nm wide, and (130+-30) nm thick. We show that these nanoflags have a Land\'e g-factor larger than InAs and InSb and a mobility comparable to those of the best performing InAs and InSb nanoflags. Besides, we show evidence for a surface Fermi level pinning in the conductance band of these InAs0.77Sb0.23 nanoflags, similar to the well-known behavior of InAs. This promises to make InAsSb easy to couple to superconductors, while keeping or improving many of the features that make InSb an interesting material for quantum applications.

cond-mat.mtrl-sci↗

arXiv2025

Supercurrent modulation in InSb nanoflag-based Josephson junctions by scanning gate microscopy

InSb nanoflags represent an interesting platform for quantum transport and have recently been exploited in the study of hybrid planar Josephson junctions. Due to the uncovered semiconductor surface, they are also good candidates for surface probe techniques. Here, we report the first Scanning Gate Microscopy (SGM) experiments on Nb-contacted InSb nanoflag-based Josephson junctions. In the normal state, sizable conductance modulation via the charged tip of the SGM is recorded. In the superconducting state, we report the first application of Scanning Gate Microscopy to superconducting weak links, demonstrating the possibility of manipulating the supercurrent flow across a semiconductor-superconductor heterostructure at a local level. The experimental findings are consistent with theoretical predictions and establish a new way of investigating the behavior of superconducting weak links, towards the local imaging of supercurrent flow.

cond-mat.supr-con↗

arXiv2025

Superconducting Quantum Interference Devices based on InSb nanoflag Josephson junctions

Planar Josephson junctions (JJs) based on InSb nanoflags have recently emerged as an intriguing platform in superconducting electronics. This letter presents the fabrication and investigation of superconducting quantum interference devices (SQUIDs) employing InSb nanoflag JJs. We provide measurements of interference patterns in both symmetric and asymmetric geometries. The interference patterns in both configurations can be modulated by a back-gate voltage, a feature well reproduced through numerical simulations. The observed behavior aligns with the skewed current-phase relations of the JJs, demonstrating significant contributions from higher harmonics. We explore the magnetic field response of the devices across a wide range of fields ($\pm 30$ mT), up to the single-junction interference regime, where a Fraunhofer-like pattern is detected. Finally, we assess the flux-to-voltage sensitivity of the SQUIDs to evaluate their performance as magnetometers. A magnetic flux noise of $S^{1/2}_\Phi = 4.4 \times 10^{-6} \Phi_0 / \sqrt{Hz}$ is identified, indicating potential applications in nanoscale magnetometry.

cond-mat.mes-hall↗