QUANTUMOPTOELECTR · Quantum Opto-Electronics

We propose to develop an opto-electronics interface between single-electron devices and single-photon optics. The ultimate limit in the miniaturization of electronics and photonics is at the nanometer scale. Here the signal level can be controlled at the fundamental level of a single electron for electricity and a single photon for light. These limits are actively being pursued for scientific interest with possible applications in the new area of quantum information science. Yet, these efforts occur separately in the distinct communities of solid state electronics and quantum optics. Here we propose to develop a toolbox for interfacing electronics and optics on the level of single electrons and photons. The basic building block is a nanoscale pn-junction defined in a semiconductor nanowire, which is the most versatile material system for single electron to single photon conversion. We will develop the following technology: (1) growth of complex semiconductor nanowires (2) quantum state transfer for copying the information stored in an electron quantum state onto a photon state (3) single-photon optical-chip with on-chip guiding via single plasmons and on-chip detection with a superconducting detector. Besides being fundamentally interesting by itself, this new toolbox opens a new area of experiments where qubits processed in solid state nano-devices are coupled quantum mechanically over long distances via photons as signal carriers to various kinds of other interesting quantum system (e.g. solid state quantum dots, confined nuclear spins and atomic vapours).