Quantum dots as single-photon sources
Confined electronic states can emit antibunched photons on demand.
Physical intuition
Confined electronic states can emit antibunched photons on demand. This is the starting point for understanding how nanoscale optical geometry changes the states or dynamics accessible to light and matter.
Deep dive: how the mechanism works
Optical or electrical excitation prepares an exciton that recombines radiatively; a cavity or waveguide channels the emitted photon.
How the quantum phenomenon appears
An InAs quantum dot embedded in a photonic crystal emits into a guided mode. To distinguish a genuinely quantum signal from a classical optical response, connect the device physics to a measurement such as photon correlations, interference visibility, energy-level structure or quantum-state tomography where appropriate.
Assumptions and limitations
Research and simulation exercise
Identify the tunable parameters, predict the observable from the stated model, and sweep one parameter while holding the others fixed. Compare against a simpler reference model, quantify loss and uncertainty, and state which observations would falsify the hypothesis.
Connect the ideas
See the chapter guide and further reading.