Skip to content Skip to navigation

Diamondoids and Diamond Color Centers

Representative structures of diamondoids and their relation with the diamond lattice.

Diamondoids

Diamondoids are cage-like hydrocarbon molecules with a C-C frame resembling that of the diamond lattice. Essentially molecular-size diamonds, they have exhibited a variety of unique properties such as monochromatic photoemission [1-2] and ultra-strong van der Waals interaction that enables unique chemical bond formation [7]. Monochromatic photoemission has been used to establish the highest resolution on X-PEEM by coating surface of magnetic domain sample with Self Assembly Monolayers of diamondoids [3].

We have the capability to separate, uniquely identify and chemically functionalize a large group of this family of molecules. Currently we are interested in several perspectives regarding the physics, chemistry and application of this novel type of diamond materials, including:

  • diamondoid-modulated self-assembly of low-dimensional nanostructures,
  • diamondoid-seeded growth of high-purity diamond, and
  • the development of diamondoid-enabled stable monochromatic photoemitter towards practical electron source for microscopy and lithography applications.


Diamond Color Centers

The diamond color is critical for future quantum and biology technologies. The nitrogen-vacancy center in diamond has been demonstrated to be a promising platform for quantum sensing and magnetometry, while the negatively charged silicon-, germanium-, lead-, and tin-vacancy have favorable optical properties and robustness to electric-field fluctuations, which are critical for the realization of future large-scale optical quantum information processing applications.

In the past decade, our group developed a complete material synthesis pipeline to incorporate a variety of color centers in diamond nanoparticles as well as bulk diamond plates. Our “Vertical Growth” method successfully embedded optically active nitrogen-vacancy centers in high-quality diamond nanoparticles down to 75 nm [4]. Recently, by combining the “shallow ion implantation and growth” (SIIG) method with the undercut fabrication technology, negatively charged tin-vacancies have been incorporated into a free-standing nano-beam device. This quantum device demonstrates superior optical properties and long spin coherence time at a temperature above 1K [5-6].

Schematic illustration of the vertical-substrate MPCVD diamond growth. [1(2,3)4]-Pentamantane was chemically bonded to oxidized surfaces of silicon wafers via phosphonyl dichloride, and then the substrate is rotated 90° to a vertical configuration for MPCVD diamond growth. The hydrogen plasma is concentrated on the top edge.

 

Schematic of the SIIG method of SnV− center generation. PL spectra at room temperature for samples A (teal) and B (purple). Site-controlled generation of SnV− centers.

 

Selected Publications

[1] W. L. Yang et al. Monochromatic electron photoemission from diamondoid monolayers. Science 316, 1460 (2007)

[2] W. A. Clay et al. The origin of monochromatic photoemission peak in diamondod monolayer. Nano Lett. 9, 56 (2009)

[3] H. Ishiwata et al. Diamondoid coating enables disruptive approach for chemical and magnetic imaging with 10 nm spatial resolution. Appl. Phys. Lett. 101, 163101 (2012)

[4] Tzeng, Yan-Kai et al. Vertical-substrate MPCVD epitaxial nanodiamond growth. Nano letters 17(3), 1489 (2017)

[5] Rugar, Alison E. et al. Generation of Tin-Vacancy Centers in Diamond via Shallow Ion Implantation and Subsequent Diamond Overgrowth. Nano letters 20(3), 1614 (2020).

[6] Rugar, Alison E. et al. Narrow-linewidth tin-vacancy centers in a diamond waveguide. (Submitted)

References

[7] P. R. Schreiner et al. Overcoming lability of extremely long alkane carbon-carbon bonds through dispersion forces. Nature 477, 308 (2011)