Fabrication of n-Type Doped V-Shaped Structures on (100) Diamond

International audienceHerein, a technological process for the fabrication of n-type doped V-shaped structures on (100) single-crystalline diamond substrates, designed to overcome the limitations of n-type doping on (100) surfaces, is presented. This doping enhancement process can be applied to realize electronic power devices such as a junction barrier Schottky diode or junction field effect transistors with low on-resistance. Herein, a catalytic etching process is performed by using square-shaped nickel masks on the diamond surface and annealing in a hydrogen atmosphere, resulting in the formation of inverted pyramidal structures with flat {111} sidewalls. The resulting V-shaped structures are subsequently overgrown with phosphorus-doped diamond to achieve n-type doped facets with higher doping concentrations. Cathodoluminescence studies reveal the predominant incorporation of phosphorus donors on the {111} sidewalls of V-shaped structures

Microstructural and optical emission properties of diamond multiply twinned particles

Multiply twinned particles (MTPs) are fascinating crystallographic entities with a number of controllable properties originating from their symmetry and cyclic structure. In the focus of our studies are diamond MTPs hosting optically active defects—objects demonstrating high application potential for emerging optoelectronic and quantum devices. In this work, we discuss the growth mechanisms along with the microstructural and optical properties of the MTPs aggregating a high-density of “silicon-vacancy” complexes on the specific crystal irregularities. It is demonstrated that the silicon impurities incite a rapid growth of MTPs via intensive formation of penetration twins on {100} facets of regular octahedral grains. We also show that the zero-phonon-line emission from the Si color centers embedded in the twin boundaries dominates in photo- and electroluminescence spectra of the MTP-based light-emitting devices defining their steady-state optical properties

Active and fast charge-state switching of single NV centres in diamond by in-plane Al-Schottky junctions

In this paper, we demonstrate an active and fast control of the charge state and hence of the optical and electronic properties of single and near-surface nitrogen-vacancy centres (NV centres) in diamond. This active manipulation is achieved by using a two-dimensional Schottky-diode structure from diamond, i.e., by using aluminium as Schottky contact on a hydrogen terminated diamond surface. By changing the applied potential on the Schottky contact, we are able to actively switch single NV centres between all three charge states NV+, NV0 and NV− on a timescale of 10 to 100 ns, corresponding to a switching frequency of 10–100 MHz. This switching frequency is much higher than the hyperfine interaction frequency between an electron spin (of NV−) and a nuclear spin (of 15N or 13C for example) of 2.66 kHz. This high-frequency charge state switching with a planar diode structure would open the door for many quantum optical applications such as a quantum computer with single NVs for quantum information processing as well as single 13C atoms for long-lifetime storage of quantum information. Furthermore, a control of spectral emission properties of single NVs as a single photon emitters – embedded in photonic structures for example – can be realized which would be vital for quantum communication and cryptography