  Vanadium dioxide (VO2) exhibits a hysteretic insulator-to-metal transition
near room temperature, forming the foundation for various forms of resistive
switching devices. Usually, these are realized in the form of two-terminal
bridge-like structures. We show here that by incorporating multiple, parallel
VO2 bridges in a single two-terminal device, a wider range of possible
characteristics can be obtained, including a manifold of addressable resistance
states. Different device configurations are studied, in which the number of
bridges, the bridge dimensions and the interbridge distances are varied. The
switching characteristics of the multibridge devices are influenced by the
thermal crosstalk between the bridges. Scanning Thermal Microscopy has been
used to image the current distributions at various voltage/current bias
conditions. This work presents a route to realize devices exhibiting highly
non-linear, multistate current-voltage characteristics, with potential
applications in e.g., tunable electronic components and novel, neuromorphic
information processing circuitry.
