Coherent Dynamics of Coupled Electron and Nuclear Spin Qubits in Diamond

Abstract

Understanding and controlling the complex environment of solid-state quantum bits is a central challenge in spintronics and quantum information science. Coherent manipulation of an individual electron spin associated with a nitrogen-vacancy center in diamond was used to gain insight into its local environment. We show that this environment is effectively separated into a set of individual proximal 13C nuclear spins, which are coupled coherently to the electron spin, and the remainder of the 13C nuclear spins, which cause the loss of coherence. The proximal nuclear spins can be addressed and coupled individually because of quantum back-action from the electron, which modifies their energy levels and magnetic moments, effectively distinguishing them from the rest of the nuclei. These results open the door to coherent manipulation of individual isolated nuclear spins in a solid-state environment even at room temperature.

Suppression of spin-bath dynamics for improved coherence of multi-spin-qubit systems

“…Examples of such systems include nitrogen-vacancy (NV) colour centres in diamond 10 , phosphorous donors in silicon 11 and quantum dots 12 . In characterizing the potential usefulness of multi-qubit systems for quantum applications, the product of the qubit density (n qb ) and the qubit coherence lifetime (T 2 ) serves as a basic figure-of-merit (FOM), FOM = n qb T 2 .…”

Electrically driven photon antibunching from a single molecule at room temperature

“…S ingle-photon emission has been observed from a variety of quantum emitters including semiconductor quantum dots [1][2][3][4] , molecules [5][6][7][8] , atoms 9 , ions 10 and colour centres in diamond [11][12][13] . Semiconductor quantum dots, in particular from III/V materials, prove to be especially fascinating tools for electrically driven single-photon generation 14 .…”

EPR Spectroscopy

“…Recent good reviews exist about EPR spectroscopic studies on photosynthesis [20][21][22] and metalloproteins [23][24][25][26]. Strongly physics-related application fields, such as quantum computing [27], electrically detected [28] and optically [29] detected EPR spectroscopy of dopants and defects in solids are left out. Furthermore, this volume does not cover technical issues that are mainly of interest to method developers rather than chemists.…”