Undergraduate quantum optics: experimental steps to quantum physics

Abstract

We report on a step-by-step-series of experiments from statistical optics with classical light to undergraduate quantum optics with single-photon states, particularly suitable to paving an introductory way to quantum phenomena. We build up a progressive process analysing temporal variations of the irradiance of light discerned by measuring the value of the non-delayed second-order correlation function g(2)(τ = 0). We demonstrate how Poisson distributed photoelectron counts from constant irradiance (g(2)(0) = 1) can be used to calibrate the apparatus. Measurements with harmonically modulated irradiance of Poissonian light give an introduction to g(2)(0) correlation analysis. After these introductory steps, we demonstrate photon bunching with (pseudo-) thermal light (g(2)(0) ≈ 2), and finally show quantum antibunching of photons in Fock states (g(2)(0) ≈ 0). All measurements are in excellent agreement with the theoretical predictions.