Silent white light: Reduction of the second-order intensity correlation coefficient

We investigate the intrawaveguide statistics manipulation of broadband light by combining semiconductor quantum dot physics with quantum optics. By cooling a quantum dot superluminescent diode to the liquid nitrogen temperature of 77 K, Blazek [] have demonstrated a temperature-dependent reduction of the second-order intensity correlation coefficient from 2 for thermal amplified spontaneous emission light to <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:msup><a:mi>g</a:mi><a:mrow><a:mo>(</a:mo><a:mn>2</a:mn><a:mo>)</a:mo></a:mrow></a:msup><a:mrow><a:mo>(</a:mo><a:mn>0</a:mn><a:mo>,</a:mo><a:mi>T</a:mi><a:mo>=</a:mo><a:mn>190</a:mn><a:mspace width="0.16em"/><a:mi mathvariant="normal">K</a:mi><a:mo>)</a:mo></a:mrow><a:mo>≈</a:mo><a:mn>1.33</a:mn></a:mrow></a:math>. Here, we model the broadband photon statistics assuming amplified spontaneous emission radiation in a pumped, saturable quantum dot gain medium. We demonstrate that, by an intensity increase due to the quantum dot occupation dynamics via the temperature-tuned quasi-Fermi levels, together with the saturation nonlinearity, a statistics manipulation from thermal Bose-Einstein statistics towards Poissonian statistics can be realized, thus producing “silent white light” with a reduced second-order correlation coefficient. Such intensity-noise-reduced broadband radiation is relevant for many applications such as optical coherence tomography, optical communication, or optical tweezers. Published by the American Physical Society 2024