Research On Diamond NV Center And Its Interaction With Two-dimensional Harmonic Oscillator

With the development of quantum information technology,people have gradually realized that a single quantum carrier has limitations in many application scenarios.Therefore,a hybrid quantum system composed of different quantum carriers has appeared.Taking the diamond NV center as an example: NV center has many advantages,it is easy for readout and manipulation,it has a long coherence time at room temperature,etc.,thus it has become one of the most popular solid-state quantum systems,which can be used in quantum computing,quantum precision measurement,quantum networks and other fields.However,NV centers have encountered challenges in in-situ electrical control,and problems have arisen in terms of multi-bit expansion(that is,to achieve the coupling between different NV centers on-chip).We notice that the acoustic modes in solids can be electrically controlled in situ with the current technology of nanoelectromechanical systems,where the phonons can maintain good coherence time and can be transmitted over long distances.Therefore,a possible idea to solve the above-mentioned challenges and problems is to develop a hybrid quantum system based on the phonon system of the nanoelectromechanical system and the NV center.The main contents of this thesis are as follows:In order to realize the hybrid quantum system,in terms of color center,a measurement platform was designed and built,including laser confocal system and microwave control system,and these experimental systems could be used for further quantum information applications.Using the NV center ensemble samples,we have measured its continuous spectral characteristics and optical detection magnetic resonance(ODMR).We use the NV center ensemble to achieve static magnetic field measurement,laying a research foundation for the subsequent use of microwave pulse sequences to improve measurement sensitivity.In terms of nano-electromechanical systems,a two-dimensional harmonic oscillator with an atomic-layer thickness is selected,and the optical detection method is used to detect the squeezing effect and the nonlinear distribution effect of a graphene mechanical resonator at high driving power.Finally,we have designed an experimental proposal for the coupling system between NV centers and nano-electro-mechanical resonators,including the preparation method of high-quality single NV center,a hybrid system with graphene resonators and NV centers coupled in a one-dimensional chain.Our studies will shed light on the spin-phonon interaction,the in-situ electrical control of NV center,and the long-range quantum state transfer of spin states via the phonon mode.