Diamond quantum nanophotonics and optomechanics

Abstract

Diamond is a promising material for the realization of quantum information technology as it hosts optically active color centers with long lived spin coherence and has material properties that allow for efficient use of photons and phonons as quantum information carriers. For many years, implementation of devices leveraging these properties was hampered by the lack of techniques for heteroepitaxial growth of pure diamond films, which prevented straightforward application of traditional nanophotonic fabrication techniques. Recently, new fabrication procedures have emerged and enabled the fabrication of nanostructures for various applications ranging from improved photon and phonon manipulation to cavity QED. Of particular importance is the development of freestanding diamond devices which has led to the creation of diamond photonic crystal cavities coupled to color centers. Such structures have enabled benchmark experiments towards the implementation of long-range, optically-mediated quantum networks. Furthermore, these procedures can also be used to engineer nanomechanical devices for creating coherent interactions between color centers and phonons, potentially enabling the creation of complementary shorter range, mechanically-mediated networks. Finally, optomechanical devices mediating photon-phonon interactions promise to gain further control over these two degrees of freedom as well as to enable the interfacing of quantum systems at vastly differing energy scales. In this chapter we trace the progression of fabrication techniques, performance benchmarks, and applications for these devices and highlight promising directions for future research.