AWESOM: Airborne Wind Energy System on Mars

Experimental investigation of turbulence in canonical wall bounded flows: Pipe flow and Taylor-Couette flow

This thesis aims to contribute to the physical understanding of turbulence in canonical flows. For that purpose, experiments are conducted in a statistically steady turbulent pipe flow, ramp-type accelerating/decelerating turbulent pipe flow and turbulent Taylor-Couette flow. For the first two flows, time-resolved data is acquired in the cross...

Ballistic Majorana nanowire devices

The dissertation reports a series of electron transport experiments on semiconductor nanowires towards realizing the hypothesized topological quantum computation. A topological quantum computer manipulates information that is stored nonlocally in the topology of a physical system. Such an operation possesses advantages over the current quantum...

Hard Superconducting Gap in InSb Nanowires

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 show such a topological state rely on proximity-induced superconductivity. However, accessing the topological properties requires an induced hard superconducting gap,...

Ballistic superconductivity in semiconductor nanowires

Semiconductor nanowires have opened new research avenues in quantum transport owing to their confined geometry and electrostatic tunability. They have offered an exceptional testbed for superconductivity, leading to the realization of hybrid systems combining the macroscopic quantum properties of superconductors with the possibility to...

Correction to: Ballistic Majorana nanowire devices (Nature Nanotechnology, (2018), 13, 3, (192-197), 10.1038/s41565-017-0032-8)

Correction to: Nature Nanotechnologyhttps://doi.org/10.1038/s41565-017-0032-8, published online 15 January 2018. The Letter reports Majorana signatures in hybrid InSb semiconductor nanowire–NbTiN superconductor devices. The devices exhibit a conductance plateau near the conductance quantum 2e²/h at bias voltages above the...

Conductance through a helical state in an Indium antimonide nanowire

The motion of an electron and its spin are generally not coupled. However in a one-dimensional material with strong spin-orbit interaction (SOI) a helical state may emerge at finite magnetic fields, where electrons of opposite spin will have opposite momentum. The existence of this helical state has applications for spin filtering and cooper...

Experimental investigation of torque hysteresis behaviour of Taylor–Couette Flow

This paper describes the hysteresis in the torque for Taylor–Couette flow in the turbulent flow regime for different shear Reynolds numbers, aspect ratios and boundary conditions. The hysteresis increases with decreasing shear Reynolds number and becomes more pronounced as the aspect ratio is increased from 22 to 88. Measurements conducted in...

Observation of Conductance Quantization in InSb Nanowire Networks

Majorana zero modes (MZMs) are prime candidates for robust topological quantum bits, holding a great promise for quantum computing. Semiconducting nanowires with strong spin orbit coupling offer a promising platform to harness one-dimensional electron transport for Majorana physics. Demonstrating the topological nature of MZMs relies on...

Revealing the band structure of InSb nanowires by high-field magnetotransport in the quasiballistic regime

The charge transport properties of individual InSb nanowires based transistors are studied at 4.2 K in the quasiballistic regime. The energy level separations at zero magnetic field are extracted from a bias voltage spectroscopy. The magnetoconductance under a magnetic field applied perpendicularly to the nanowire axis is investigated up to...

Internal shear layers and edges of uniform momentum zones in a turbulent pipe flow

This paper provides an experimental investigation on the internal shear layers and the edges of the uniform momentum zones (UMZs) in a turbulent pipe flow. The time-resolved stereoscopic particle image velocimetry data are acquired in the cross-section of the pipe, and span the range of Reynolds number Reτ=340--1259. In the first part of the...

Spin-Orbit Protection of Induced Superconductivity in Majorana Nanowires

Spin-orbit interaction (SOI) plays a key role in creating Majorana zero modes in semiconductor nanowires proximity coupled to a superconductor. We track the evolution of the induced superconducting gap in InSb nanowires coupled to a NbTiN superconductor in a large range of magnetic field strengths and orientations. Based on realistic...

Low disorder and high valley splitting in silicon

The electrical characterisation of classical and quantum devices is a critical step in the development cycle of heterogeneous material stacks for semiconductor spin qubits. In the case of silicon, properties such as disorder and energy separation of conduction band valleys are commonly investigated individually upon modifications in selected...

Effective support set selection for few-shot detection of floating marine debris

Marine litter, particularly plastic debris, poses a significant environmental challenge globally. Detecting floating debris in the marine environment using satellite remote sensing remains a complex task due to the limited availability of high-resolution data and the coarseness of existing datasets. This study explores the potential of active...