| People | Locations | Statistics |
|---|---|---|
| Naji, M. |
| |
| Motta, Antonella |
| |
| Aletan, Dirar |
| |
| Mohamed, Tarek |
| |
| Ertürk, Emre |
| |
| Taccardi, Nicola |
| |
| Kononenko, Denys |
| |
| Petrov, R. H. | Madrid |
|
| Alshaaer, Mazen | Brussels |
|
| Bih, L. |
| |
| Casati, R. |
| |
| Muller, Hermance |
| |
| Kočí, Jan | Prague |
|
| Šuljagić, Marija |
| |
| Kalteremidou, Kalliopi-Artemi | Brussels |
|
| Azam, Siraj |
| |
| Ospanova, Alyiya |
| |
| Blanpain, Bart |
| |
| Ali, M. A. |
| |
| Popa, V. |
| |
| Rančić, M. |
| |
| Ollier, Nadège |
| |
| Azevedo, Nuno Monteiro |
| |
| Landes, Michael |
| |
| Rignanese, Gian-Marco |
|
Gorbachev, Roman V.
University of Manchester
in Cooperation with on an Cooperation-Score of 37%
Topics
Publications (11/11 displayed)
- 2020Atomic Resolution Imaging of CrBr 3 using Adhesion-Enhanced Gridscitations
- 2020Atomic Resolution Imaging of CrBr3 using Adhesion-Enhanced Gridscitations
- 2019Formation and healing of defects in atomically thin GaSe and InSecitations
- 2019Indirect to direct gap crossover in two-dimensional InSe revealed by angle-resolved photoemission spectroscopycitations
- 2018Infrared-to-violet tunable optical activity in atomic films of GaSe, InSe, and their heterostructurescitations
- 2018Unusual Suppression of the Superconducting Energy Gap and Critical Temperature in Atomically Thin NbSe2citations
- 2018Nanometer Resolution Elemental Mapping in Graphene-based TEM Liquid Cellscitations
- 2018Anomalous twin boundaries in two dimensional materialscitations
- 2017Observing imperfection in atomic interfaces for van der Waals heterostructurescitations
- 2016High electron mobility, quantum Hall effect and anomalous optical response in atomically thin InSecitations
- 2016High electron mobility, quantum Hall effect and anomalous optical response in atomically thin InSecitations
Places of action
| Organizations | Location | People |
|---|
article
Unusual Suppression of the Superconducting Energy Gap and Critical Temperature in Atomically Thin NbSe2
Abstract
It is well-known that superconductivity in thin films is generally suppressed with decreasing thickness. This suppression is normally governed by either disorder-induced localization of Cooper pairs, weakening of Coulomb screening, or generation and unbinding of vortex–antivortex pairs as described by the Berezinskii–Kosterlitz–Thouless (BKT) theory. Defying general expectations, few-layer NbSe2, an archetypal example of ultrathin superconductors, has been found to remain superconducting down to monolayer thickness. Here, we report measurements of both the superconducting energy gap Δ and critical temperature TC in high-quality monocrystals of few-layer NbSe2, using planar-junction tunneling spectroscopy and lateral transport. We observe a fully developed gap that rapidly reduces for devices with the number of layers N ≤ 5, as does their TC. We show that the observed reduction cannot be explained by disorder, and the BKT mechanism is also excluded by measuring its transition temperature that for all N remains very close to TC. We attribute the observed behavior to changes in the electronic band structure predicted for mono- and bi- layer NbSe2 combined with inevitable suppression of the Cooper pair density at the superconductor-vacuum interface. Our experimental results for N > 2 are in good agreement with the dependences of Δ and TC expected in the latter case while the effect of band-structure reconstruction is evidenced by a stronger suppression of Δ and the disappearance of its anisotropy for N = 2. The spatial scale involved in the surface suppression of the density of states is only a few angstroms but cannot be ignored for atomically thin superconductors.