Silicon nanowire field-effect transistors

Silicon nanowire field-effect transistors

We have always been open to side-projects leading to applications. One was CNT reinforced composites where we have written an influential patent. The other is the exploration of ion-sensitive field-effect transistors for biochemical sensing. Though there was a substantial literature,

Graphene spintronics

Graphene spintronics

We have demonstrated efficient spin-injection into graphene using h-BN as tunneling barrier. We have used CVD-grown h-BN on CVD graphene, as well as few layer h-BN on a graphene h-BN stack. We have also looked into tunneling barriers made from

Nanodevices with ferromagnetic elements

Nanodevices with ferromagnetic elements

Ferromagnetic contacts can induce an exchange field into a nanodevice, but can also be used as a source of spin-polarized electrons and detector. In the latter case, so called tunneling magneto-resistance (TMR) devices are obtained when at least two contacts

Superconducting quantum dot hybrid devices

Superconducting quantum dot hybrid devices

We were one of the first group (if not the first) looking into QDs that are coupled to superconductors (SCs).1  Our devices were realized with carbon nanotubes CNTs and semiconducting nanowires (SNWs). In our early studies we were intrigued by

Quantum devices probed at microwave frequencies

Quantum devices probed at microwave frequencies

In the framework of the ERC advanced research project QUEST, we have developed a versatile high-frequency setup that works in the frequency window 1-10 GHz and allows for high-resolution reflectance and noise measurements. In order to apply this to high

Charge Correlations by Shot Noise Measurements

Charge Correlations by Shot Noise Measurements

Our groups has been pioneering shot-noise measurements in nanodevices.1 We have studied noise in various geometries, in the single-electron tunneling device,2 in diffusive wires,3,4 in metallic S-N devices,5 in ballistic cavities6 and in quantum Hall devices where we could demonstrate

Majorana fermions in nanowire-based quantum devices

Majorana fermions in nanowire-based quantum devices

Bottom-up grown single-crystalline semiconducting nanowires (SNWs) are very versatile systems, since quantum dots can readily be defined using external finger gate electrodes. Due to the large g-factor and large spin-orbit interaction, SNWs are a hot topic today, since one-dimensional helical

Quantum transport in graphene

Quantum transport in graphene

Ballistic graphene offers a promising platform for electron optical devices. We have developed a versatile technology that allows to suspend graphene and complement it with arbitrary bottom and top-gate structures.1 Using current annealing we demonstrated exceptional high nobilities approaching 102