Silicon incorporation in CVD diamond layers

Quantum sensing of microRNAs with nitrogen-vacancy centers in diamond

Label-free detection of nucleic acids such as microRNAs holds great potential for early diagnostics of various types of cancers. Measuring intrinsic biomolecular charge using methods based on field effect has been a promising way to accomplish label-free detection. However, the charges of biomolecules are screened by counter ions in solutions over a short distance (Debye length), thereby limiting the sensitivity of these methods. Here, we measure the intrinsic magnetic noise of paramagnetic counter ions, such as Mn2+, interacting with microRNAs using nitrogen-vacancy (NV) centers in diamond. All-atom molecular dynamics simulations show that microRNA interacts with the diamond surface resulting in excess accumulation of Mn ions and stronger magnetic noise. We confirm this prediction by observing an increase in spin relaxation contrast of the NV centers, indicating higher Mn2+ local concentration. This opens new possibilities for next-generation quantum sensing of charged biomolecules, overcoming limitations due to the Debye screening.

High-pressure crystallization and properties of diamond from magnesium-based catalysts

HPHT diamond synthesis using catalysts based on magnesium demonstrates a number of intriguing characteristics. In this highlight, we review the major characteristics of the growth, morphology, internal structure, and defect and impurity content of diamonds crystallized using Mg-based catalysts.

High-pressure synthesis and characterization of diamond from an Mg–Si–C system

High-pressure synthesis of silicon-doped diamond from the Mg–Si–C system is demonstrated. The effects of Si on the crystallization and spectroscopic characteristics of diamond are established.