A semiconductor-superconductor hybrid device comprises a semiconductor, a superconductor, and a barrier between the superconductor and the semiconductor. The device is configured to enable energy level hybridisation between the semiconductor and the superconductor. The barrier is configured to increase a topological gap of the device. The barrier allows for control over the degree of hybridisation between the semiconductor and the superconductor. Further aspects provide a quantum computer comprising the device, a method of manufacturing the device, and a method of inducing topological behaviour in the device.