Wide-bandgap quantum nanowire electronics (Prof. Krstić)
Quasi-1D nanowires represent excellent low-dimensional fermionic systems, which can show increased conductivity and mobility due to their low dimensionality and can be accompanied by increased phase coherence lengths. Also, interactions within such low-dimensional systems can lead to the formation of correlated, topological and (macroscopic) quantum states, such as for instance charge and spin density waves.
These properties make quantum nanowires potential candidates for quantum/topology electronic and optical information processing.
In this respect, semiconductor nanowires with a comparatively small band gap, e.g. based on Ge, are and continue to be intensively investigated in regard to quantum physical aspects. In comparison, the field of quantum electronics with wide-bandgap semiconductors is at its beginning, although these types of semiconductors are already being investigated in particular in quantum optics (cf. color centers, defects).
In the context of this research area electronics of semiconductor quantum nanowires, the semiconductor 4H-SiC is at the center of our activities, whereby the first research steps with GaN nanowires are also taking place.
We manufacture the quantum nanowires ourselves using suitable etching processes and thus achieve cross-sectional nanowire dimensions of up to 20 nm and lengths of a few µm. We investigate the properties of these quantum nanowires and corresponding devices predominantly by means of electrical transport.
- Kolesnik-Gray M., Lutz T., Collins G., Biswas S., Holmes JD., Krstic V.:
Contact resistivity and suppression of Fermi level pinning in side-contacted germanium nanowires
In: Applied Physics Letters 103 (2013), Article No.: 153101
- Connaughton S., Hobbs R., Lotty O., Holmes JD., Krstic V.:
Variation of self-seeded germanium nanowire electronic device functionality due to synthesis condition determined surface states
In: Advanced Materials Interfaces 2 (2015), Article No.: 1400469
- Kolesnik-Gray M., Sorger C., Biswas S., Holmes JD., Weber HB., Krstic V.:
In operandi observation of dynamic annealing: A case study of boron in germanium nanowire devices
In: Applied Physics Letters 106 (2015), Article No.: 233109
- Connaughton S., Kolesnik-Gray M., Hobbs R., Lotty O., Holmes JD., Krstic V.:
Diameter-driven crossover in resistive behaviour of heavily doped self-seeded germanium nanowires
In: Beilstein Journal of Nanotechnology 7 (2016), p. 1284-1288
- Kolesnik-Gray M., Collins G., Holmes JD., Krstic V.:
Fingerprints of a size-dependent crossover in the dimensionality of electronic conduction in Au-seeded Ge nanowires
In: Beilstein Journal of Nanotechnology 7 (2016), p. 1574–1578