Quantum Many-Body Theory for kq-Deformed Particles

Abstract: We present a comprehensive quantum many body theory for kq deformed particles, offering a novel framework that relates particle statistics directly to effective interaction strength. Deformed by the parameters k and q, these particles exhibit statistical behaviors that interpolate between conventional bosonic and fermionic systems, enabling us to model complex interactions via statistical modifications. We develop a generalized Wick's theorem and extended Feynman diagrammatic tailored to kq-particles, allowing us to calculate two types of Green functions. Explicit expressions for these Green functions are derived in both direct and momentum spaces, providing key insights into the collective properties of kq-deformed systems. Using a random phase approximation (RPA), we estimate the dielectric function for q-fermion gas, and analyze the Friedel oscillations, the plasmon excitations, and the energy loss function. Our results demonstrate that the effective interaction is tuned by the value of q, so that a non interacting limit is obtained as q goes to zero, where the Friedel as well as the plasma oscillations disappear. There is an optimal value of q, the plasma frequency, as well as the energy loss function show an absolute maximum, and the effective interaction changes behavior.