papers

Publications (28)

cond-mat.mes-hall2021

Large zero-bias peaks in InSb-Al hybrid semiconductor-superconductor nanowire devices

Hao Zhang, Michiel W. A. de Moor, Jouri D. S. Bommer +19

We report electron transport studies on InSb-Al hybrid semiconductor-superconductor nanowire devices. Tunnelling spectroscopy is used to measure the evolution of subgap states whil…

cond-mat.mes-hall2023

Mid-Infrared Detectors and Imagers Integrating All-Group IV Nanowires

Lu Luo, Mahmoud RM Atalla, Simone Assali +3

Cost-effective mid-wave infrared (MWIR) optoelectronic devices are of utmost importance to a plethora of applications such as night vision, thermal sensing, autonomous vehicles, fr…

cond-mat.mes-hall2017

Quantized Majorana conductance

Hao Zhang, Chun-Xiao Liu, Sasa Gazibegovic +19

Majorana zero-modes hold great promise for topological quantum computing. Tunnelling spectroscopy in electrical transport is the primary tool to identify the presence of Majorana z…

cond-mat.mes-hall2022

Atomic fluctuations lifting the energy degeneracy in Si/SiGe quantum dots

Brian Paquelet Wuetz, Merritt P. Losert, Sebastian Koelling +16

Electron spins in Si/SiGe quantum wells suffer from nearly degenerate conduction band valleys, which compete with the spin degree of freedom in the formation of qubits. Despite att…

cond-mat.mes-hall2021

Epitaxy of Advanced Nanowire Quantum Devices

Sasa Gazibegovic, Diana Car, Hao Zhang +20

Semiconductor nanowires provide an ideal platform for various low-dimensional quantum devices. In particular, topological phases of matter hosting non-Abelian quasi-particles can e…

physics.app-ph2024

Extended-SWIR High-Speed All-GeSn PIN Photodetectors on Silicon

Mahmoud R. M. Atalla, Cedric Lemieux-Leduc, Simone Assali +3

There is an increasing need for silicon-compatible high bandwidth extended-short wave infrared (e-SWIR) photodetectors (PDs) to implement cost-effective and scalable optoelectronic…

cond-mat.mtrl-sci2025

Three-dimensional atom-by-atom mapping of nanoscale precipitates in single Te inclusions in Cd0.9Zn0.1Te crystal

Eloïse Rahier, Sebastian Koelling, Guillaume Nadal +3

The complexity and richness of phenomena governing alloy crystal growth can be unraveled by examining the three-dimensional atomic-level distribution of elements and impurities inc…

cond-mat.mes-hall2019

Selective-area chemical beam epitaxy of in-plane InAs one-dimensional channels grown on InP(001), InP(111)B, and InP(110) surfaces

Joon Sue Lee, Sukgeun Choi, Mihir Pendharkar +15

We report on the selective-area chemical beam epitaxial growth of InAs in-plane, one-dimensional (1-D) channels using patterned SiO-coated InP(001), InP(111)B, and InP(110) s…

cond-mat.mtrl-sci2022

Micrometer-thick, atomically random Si0.06Ge0.90Sn0.04 for silicon-integrated infrared optoelectronics

Simone Assali, Anis Attiaoui, Sebastian Koelling +6

A true monolithic infrared photonics platform is within reach if strain and bandgap energy can be independently engineered in SiGeSn semiconductors. Herein, we investigate the stru…

cond-mat.mes-hall2024

Hard superconducting gap in InSb nanowires

Önder Gül, Hao Zhang, Folkert K. de Vries +14

Topological superconductivity is a state of matter that can host Majorana modes, the building blocks of a topological quantum computer. Many experimental platforms predicted to sho…

physics.optics2022

Extended-SWIR Photodetection in All-Group IV Core/Shell Nanowires

Lu Luo, Simone Assali, Mahmoud R. M. Atalla +6

Group IV Ge1-xSnx semiconductors hold the premise of enabling broadband silicon-integrated infrared optoelectronics due to their tunable bandgap energy and directness. Herein, we e…

physics.optics2023

Mid-infrared top-gated Ge/GeSn nanowire phototransistors

Lu Luo, Mahmoud RM Atalla, Simone Assali +2

Achieving high crystalline quality GeSn semiconductors at Sn content exceeding 10\% is quintessential to implementing the long sought-after silicon-compatible mid-inf…

cond-mat.mes-hall2021

Growth of PbTe nanowires by Molecular Beam Epitaxy

Sander G. Schellingerhout, Eline J. de Jong, Maksim Gomanko +8

Advances in quantum technology may come from the discovery of new materials systems that improve the performance or allow for new functionality in electronic devices. Lead tellurid…

cond-mat.mtrl-sci2020

Kinetic Control of Morphology and Composition in Ge/GeSn Core/Shell Nanowires

Simone Assali, Roberto Bergamaschini, Emilio Scalise +8

The growth of Sn-rich group-IV semiconductors at the nanoscale provides new paths for understanding the fundamental properties of metastable GeSn alloys. Here, we demonstrate the e…

cond-mat.mes-hall2021

Probing embedded topological modes in bulk-like GeTe-SbTe heterostructures

Hisao Nakamura, Johannes Hofmann, Nobuki Inoue +5

The interface between topological and normal insulators hosts metallic states that appear due to the change in band topology. While these topological states at a surface, i.e., a t…

cond-mat.mes-hall2021

In-plane selective area InSb-Al nanowire quantum networks

Roy L. M. Op het Veld, Di Xu, Vanessa Schaller +19

Strong spin-orbit semiconductor nanowires coupled to a superconductor are predicted to host Majorana zero modes. Exchange (braiding) operations of Majorana modes form the logical g…

physics.optics2025

Mid-infrared group-IV nanowire laser

Youngmin Kim, Simone Assali, Junyu Ge +10

Semiconductor nanowires have shown great potential for enabling ultra-compact lasers for integrated photonics platforms. Despite the impressive progress in developing nanowire lase…

cond-mat.mes-hall2021

Te-doped selective-area grown InAs nanowires for superconducting hybrid devices

Pujitha Perla, Anton Faustmann, Sebastian Koelling +11

Semiconductor nanowires have emerged as versatile components in superconducting hybrid devices for Majorana physics and quantum computing. The transport properties of nanowires can…

physics.app-ph2026

Reduced Dark Current in Cd0.9Zn0.1Te Detector Arrays by Aluminium Oxide Passivation

Sudarshan Singh, Luc Montpetit, Eloïse Rahier +3

Contrary to the prevailing view that processing cadmium zinc telluride (CZT) semiconductors above 150 °C leads to irreversible device degradation, here we show that Al2O3 passivat…

physics.app-ph2024

Transfer-printed multiple GeSn membrane mid-infrared photodetectors

Cédric Lemieux-Leduc, Mahmoud R. M. Atalla, Simone Assali +8

Due to their narrow band gap and compatibility with silicon processing, germanium-tin (GeSn) alloys are a versatile platform for scalable integrated mid-infrared photon…

cond-mat.mtrl-sci2025

Spontaneous Transition from Conformal to Two-Dimensional Growth in Ge/GeSn Core/Shell Nanowires

Simone Assali, Sebastian Koelling, Milenka Andelic +3

GeSn semiconductors are group-IV isovalent alloys that offer remarkable tunability of optoelectronic properties across the entire infrared spectrum, while remaining fully compatibl…

cond-mat.mes-hall2017

Ballistic superconductivity in semiconductor nanowires

Hao Zhang, Önder Gül, Sonia Conesa-Boj +19

Semiconductor nanowires have opened new research avenues in quantum transport owing to their confined geometry and electrostatic tunability. They have offered an exceptional testbe…

physics.app-ph2021

Recrystallization and Interdiffusion Processes in Laser-Annealed Strain-Relaxed Metastable GeSn0

Salim Abdi, Simone Assali, Mahmoud R. M. Atalla +3

The prospect of GeSn semiconductors for silicon-integrated infrared optoelectronics brings new challenges related to the metastability of this class of materials. As a matter of fa…

physics.app-ph2022

Dark current in monolithic extended-SWIR GeSn PIN photodetectors

Mahmoud R. M. Atalla, Simone Assali, Sebastian Koelling +2

The monolithic integration of extended short-wave infrared (e-SWIR) photodetectors (PDs) on silicon is highly sought-after to implement manufacturable, cost-effective sensing and i…

physics.app-ph2026

Epitaxy of strained, nuclear-spin free Ge quantum wells from solid source materials

Maximilian Oezkent, Chen-Hsun Lu, Lucas Becker +13

Germanium quantum well heterostructures have rapidly emerged as a leading platform for solid-state quantum information processing; however, material quality limits scalability, and…

cond-mat.mtrl-sci2022

500-period epitaxial Ge/Si0.18Ge0.82 multi-quantum wells on silicon

Simone Assali, Sebastian Koelling, Zeinab Abboud +3

Ge/SiGe multi-quantum well heterostructures are highly sought-after for silicon-integrated optoelectronic devices operating in the broad range of the electromagnetic spectrum cover…

physics.optics2023

Continuous-wave GeSn light emitting diodes on silicon with m room-temperature emission

Mahmoud R. M. Atalla, Simone Assali, Gérard Daligou +4

Silicon-compatible short- and mid-wave infrared emitters are highly sought-after for on-chip monolithic integration of electronic and photonic circuits to serve a myriad of applica…

cond-mat.mtrl-sci2021

Electronic Structure and Epitaxy of CdTe Shells on InSb Nanowires

Ghada Badawy, Bomin Zhang, Tomáš Rauch +10

Indium antimonide (InSb) nanowires are used as building blocks for quantum devices because of their unique properties, i.e., strong spin-orbit interaction and large Landé g-factor…