Quantum-Grade Diamond

Diamond specified for a particular quantum defect system and measurement method.

Good to know

Nitrogen-vacancy centres are one option, not the definition of every quantum-grade material.
Impurity concentration, defect density and surface condition affect characterization.

What we define for quantum-grade diamond, with units and how each is typically measured. We confirm values for your application in technical review.

Parameter	Unit	Typical test method
Lateral size, outline or diameter, and tolerance	mm	Optical measurement
Thickness and tolerance (bulk or layer)	mm	Micrometer or optical gauge
Edge condition and chip limit		Microscopy inspection to drawing

Parameter	Unit	Typical test method
Colour-centre species and concentration	ppb	EPR or photoluminescence spectroscopy
Carbon isotope composition	%	SIMS or Raman spectroscopy
Nitrogen content and detection limit	ppb or ppm	FTIR spectroscopy or SIMS
Spin coherence time	µs	Spin-echo or Ramsey measurement
Face orientation, edge orientation and miscut		XRD or Laue diffraction
Inclusions, growth sectors and defects		Cross-polarised microscopy or birefringence imaging
Crystalline quality (rocking-curve width)	arcsec	XRD rocking curve
Raman linewidth of the diamond line	cm⁻¹	Raman spectroscopy
Growth sectors and internal strain		Cross-polarised microscopy or birefringence imaging

Parameter	Unit	Typical test method
Surface finish condition (as-grown, lapped or polished)		Visual inspection to drawing
Surface roughness per side	nm Ra	Profilometry or AFM

Parameter	Unit	Typical test method
Packaging, cleanliness and labelling		Per drawing
Certificate of conformance and traceability		Supplier declaration

Requirement to review

Share your quantum-grade diamond requirement, dimensions and drawing for review.