Modulation of recombination radiation in quantum wires by electric field and the possibility of its application in quantum electronics

Abstract: The cross section for the process of single-photon recombination of free charge carriers in the 1D geometry of a thin quantum wire in a strong longitudinal electric field is calculated. It is established that the spectrum of recombination radiation is no less pure (close to sparse discrete) and stable than that of quantum dots. It is believed that the longitudinal classical degree of freedom “blurs” spectral lines due to the uncertainty in the kinetic energy of the longitudinal motion of carriers. It is shown that a strong electric field removes this uncertainty, while making it possible to vary both the frequency of radiation and the intensity of the recombination process. A complex oscillatory dependence of the recombination intensity on the uniform electric field strength is revealed. The natural directionality of the radiation along the wire in a strong field is an additional advantage. The semiclassical approach made it possible to establish that the recombination process is predominantly localized in the vicinity of particular points of the wire, where the dispersion relations for the emitted photon are satisfied. The electric field can affect the position of these points and modulate the spatial distribution, spectrum and anisotropy of recombination radiation. The theoretical results obtained are used to interpret extensive experimental studies on recombination radiation from CdSe filaments in an electric field.

Keywords: thin quantum wires, longitudinal strong electric field, monochromatic directed recombination radiation with controlled characteristics.