Quantum noise and spatial emission properties of RCLEDs

Abstract

We present results of comprehensive investigations of the intensity noise and the angular-resolved spectral emission characteristics of resonant-cavity light-emitting diodes (RCLEDs), demonstrating an interesting interplay between these two properties. First, we find that the intensity noise of the investigated RCLEDs, detected within a full solid angle of detection, is up to -0.15 dB below the shot noise in a quite large pumping regime, i.e., we demonstrate the successful generation of squeezed states of light with these optoelectronic devices. Second, we investigate the spectral and angular emission characteristics and find that the cavity-like character of the Bragg mirrors and the quantum well active medium manifests itself in a blue shift of the central emission wavelength from 847 nm at zero degree to 825 nm at an emission angle of sixty degree. By varying the temperature we are able to detune the quantum-well emission wavelength and the cavity resonance wavelength and observe a broader angular intensity profile. Third, we measure the angular resolved intensity noise. Its super-shot noise behavior can be explained by anticorrelations between radial components of the output intensity emitted at different angles. Finally, the possible origin of the observed anticorrelations in the angular-resolved intensity noise, as well as possibilities for future trends, applications and the limitations of these non-classical states of light with respect to sensing and spectroscopic applications are discussed.