Quantum Coherent Modulation Of Diamond Germanium Vacancy Color Center Optical Pulse Transmission

Since the advent of laser,because of its superior optical performance,it has received extensive attention.Researchers have conducted in-depth research on related disciplines such as quantum optics,laser physics,and nonlinear optics.Atomic coherence and quantum interference have always been the focus of the researches in quantum optics and atomic physics field.Especially,electromagnetically induced transparency(EIT)exhibits exceptional attraction to researchers because it can not only reduce the absorption of the medium but also modify the dispersion of the medium.Therefore,based on EIT,the probe pulse could propagate with ultraslow group velocity,and the lossless propagation comes into being.This research plays an important role in the optical manipulating and processing of quantum information.However,traditional materials cannot be further developed due to their inherent optical properties.Therefore,it is urgent to study the optical pulse propagation in new materials,and the quantum coherence manipulating of pulse propagation.As a new kind of dot defect color center,compared with the atomic system and other diamond color centers such as nitrogen vacancy(NV)centers,silicon vacancy(SiV)centers,the diamond germanium-vacancy(GeV)color centers have a higher quantum efficiency in optical transitions,a larger energy splitting in the ground state and a long electronic spin coherence.Moreover,it also has a higher optical stability.In summary,it is a good choice to achieve stable and lossless pulse propagation in this solid-state system.In this paper,by acquiring the inspiration from the concept of EIT and the excellent optical properties of GeV color centers,the characteristics of optical pulse propagation are studied in this solid-state quantum system,and we theoretically realized a stable optical pulse propagation,which provides a certain reference for the realization of lossless propagation of optical pulses in solid-state quantum systems.The main structure of this article is as follows:1.We introduced the research background and current situation of optical pulse propagation,optical solitons,and the diamond germanium vacancy(GeV)color centers system respectively.And the formation principle of optical solitons was briefly introduced.The GeV color centers stand out for its optical performance,which is different from previous studies of solid-state systems,and has more advantages for our research on optical pulse propagation.2.The semi-classical theory of the interaction between light and matter is the theoretical basis for the realization of quantum coherent regulation of optical pulse propagation.In the second part we introduced this theory.The content of this part is mainly divided into the following subsections:electric-dipole approximation,rotating-wave approximation,slow-varying envelope approximation,probability amplitude method,density matrix method,light propagation theory in atomic medium,and electromagnetic induction transparency principle.3.In this section,the main work of this article(quantum coherent manipulating of pulse propagation)was discussed in detail.we investigated the quantum coherence manipulating of the pulse propagation in a solid-state system which is filled with a four-level N-type diamond germanium-vacancy defect centers under optical excitation.These results reviewed that the propagation property of the probe pulse was controlled by the probe detuning,the intensities and detunings of the control fields as well as the number densities of GeV color centers based on quantum coherence.Under appropriate parameters,the stable pulse propagation with ultraslow group velocity was acquired based on EIT.4.Finally,we summarized the content of the research in this paper,and looked forward to the future prospects of the theory and application of optical pulse propagation in the germanium vacancy color center.