Synthetic Diamond Emission Line Narrowing via Multi-Stage Annealing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current synthetic diamond materials for quantum and optical applications suffer from broad emission line widths due to spectral diffusion and inhomogeneous broadening, leading to low photon collection efficiency and long data acquisition times, which hinders the realization of multi-photon quantum interference and entanglement.

Innovation Solution

A synthetic diamond material with spin defects is developed using a multi-stage annealing process to achieve a full width half maximum intrinsic inhomogeneous zero phonon line width of no more than 100 MHz, stabilized over time, within a CVD synthetic diamond material, which reduces spectral diffusion and enhances emission line stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If conventional synthetic diamond materials are used, then the material can be synthesized with standard processes, but the emission line width is broad due to spectral diffusion and inhomogeneous broadening

Engineering Contradiction:
Improveemission line widthVSAvoidmulti-stage annealing process
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by performing multiple annealing treatments before the final measurement and application of the diamond material. The multi-stage annealing process (including treatments at different temperatures and atmospheres) is conducted in advance to pre-establish the narrow emission line width and reduce spectral diffusion, ensuring the material is optimally prepared before quantum applications.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent utilizes parameter changes by systematically varying annealing temperature, atmosphere composition, and treatment duration to optimize the emission characteristics. Different annealing stages use different parameters (e.g., temperature ranges from 700°C to 1500°C, different gas atmospheres) to progressively improve the zero phonon line width and reduce inhomogeneous broadening.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If standard CVD diamond synthesis is used, then the synthesis process is simple and fast, but photon collection efficiency is low due to broad emission lines

Engineering Contradiction:
Improvephoton collection efficiencyVSAvoiddata acquisition time
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent applies parameter changes by optimizing the annealing temperature, atmosphere, and duration to achieve narrow emission line widths. This results in transform-limited or near transform-limited zero phonon lines, which directly improve photon collection efficiency by reducing spectral diffusion and inhomogeneous broadening, thereby reducing data acquisition times for quantum applications.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent replaces conventional single-step synthesis methods with a multi-stage annealing process that uses thermal and atmospheric parameters to achieve the desired emission characteristics. This substitution of process methodology enables precise control over emission line width and photon collection efficiency.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If conventional annealing processes are used, then the process is simple and quick, but spectral diffusion and inhomogeneous broadening persist

Engineering Contradiction:
Improveemission line stabilityVSAvoidmulti-stage annealing process
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by performing multiple annealing treatments before the final measurement and application of the diamond material. The multi-stage annealing process (including treatments at different temperatures and atmospheres) is conducted in advance to pre-establish the narrow emission line width and reduce spectral diffusion, ensuring the material is optimally prepared before quantum applications.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent applies continuity of useful action by implementing a continuous multi-stage annealing process where each stage builds upon the previous one. The annealing treatments are performed in sequence without interruption, with each stage contributing to the progressive reduction of spectral diffusion and inhomogeneous broadening, maintaining continuous improvement of emission characteristics throughout the process.

Inventive Principle:
Principle #20Continuity of useful action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach results in improved photon collection efficiency and reduced data acquisition times, enabling more efficient multi-photon quantum interference and entanglement, crucial for advanced quantum processing and sensing applications.

Implementation Method 1

annealing the synthetic diamond material using a multi-stage annealing process comprising: a first annealing step at a temperature in a range 350 to 450°C for at least 2 hours; a second annealing step at a temperature in a range 750 to 900°C for at least 2 hours; and a third annealing step at a temperature in a range 1150°C to 1550°C for at least 2 hours

Methodology Applied
Scientific EffectAnnealing: Annealing

Data Source

PatentEP2931947B1Synthetic diamond materials for quantum and optical applications and methods of making the same
Publication Date: 2019.02.13 ELEMENT SIX TECH LTD
  • EP2931947B1 patent drawingFigure 1
  • EP2931947B1 patent drawingFigure 2(a)~2(b)
  • EP2931947B1 patent drawingFigure 3(a)~3(b)

AI summary

A synthetic diamond material comprising one or more spin defects having a full width half maximum intrinsic inhomogeneous zero phonon line width of no more than 100 MHz. The method for obtain such a material involves a multi-stage annealing process.