Preparation and physical characterization of magnetic and superconducting atom-thick layers and nanowires

• Grant number: 15/02087-1
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: May 01, 2015
• End date: April 30, 2016
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Kleber Roberto Pirota
• Grantee: Román López Ruiz
• Supervisor: Eugenio Coronado
• Host Institution: Instituto de Física Gleb Wataghin (IFGW). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Institution abroad: Universitat de València, Spain
• Associated to the scholarship: 13/13275-8 - Finite-size effects, synthesis and magnetic properties of heterogeneous modelled nanowires, BP.PD

Abstract

The main objective of this project is to apply novel chemical techniques to synthesize materials of one dimension (nanowires of either Sn or Ta or Nb dichalcogenides with diameters smaller than the coherence length) or two dimensions (layers of TaS2, NbS2 and NbSe2 fwith thicknesses ranging from one to several atomic layers) which behave as superconductors at low temperatures, and to study their physical properties. We aim to introduce superconductivity and magnetism in the research of 2D systems, similar to graphene, in which this behavior has not been found yet. The magnetic properties of these systems remain unexplored due to the short number of available samples and the huge challenge that represents the detection of their minute magnetic responses. In order to face this challenge, we propose here to use a combination of local probe microscopies (AFM and MFM) and highly sensitive microsensors, such as micro-SQUID susceptometers and micro-Hall magnetometers, in order to explore in situ the effects of the low dimensionality. Suitable methods, based on in-solution deposition or exfoliation techniques, will be developed in order to optimize the coupling of the samples to the sensors, down to the limit of a single layer or an individual nanowire. We expect to measure equilibrium superconductor phase diagrams and dynamical phenomena, such as vortices or "phase-slips". The ability to fabricate and manipulate superconducting nanowires or atomic layers could open multiple perspectives in the development of superconducting electronics, from RF resonators to SQUIDs, which can find applications as magnetic sensors, as well as in metrology, medicine, and information technologies. (AU)