Figure 1
From: Driving a Superconductor to Insulator Transition with Random Gauge Fields
Tuning Random Gauge Fields.
(a) Schematic sample measurement setup. A uniform magnetic field B is applied perpendicular to the sample plane. (b) Scanning electron microscope image of an amorphous Bi nano-honeycomb film. The overlaid green network of links defining individual array cells was obtained using a triangulation method. (c) Magnified region of (b) showing dots to denote nodes. (d) Distribution of cell areas defined by the links between nodes with its Gaussian fit (red line: 
 nm2 and σ = ΔS =0.92 × 103 nm2). (e–h) Maps of the deviation of the magnetic flux through a cell from the average value, δϕ, in units of the flux quantum, ϕ0, for commensurate fields 
, 1, 2 and 3. The random variations in δϕ imply random variations in the line integral of the gauge field Aij along links that grow proportionally with 
. (i) Sheet resistance as a function of inverse temperature at commensurate magnetic fields that are well below the estimated upper critical magnetic field for this RN = 20 kΩ film. The R(T) at low temperatures evolve from superconducting to insulating characteristics with increasing 
(see text).
