Dynamic control of spontaneous emission rate using tunable hyperbolic metamaterials

Area of Science:

• Optics and Photonics
• Materials Science
• Quantum Optics

Background:

• Spontaneous emission rate of quantum emitters is crucial for quantum technologies.
• Hyperbolic metamaterials (HMMs) offer unique optical properties due to their hyperbolic dispersion.
• Tunable HMMs can dynamically modify the optical environment of emitters.

Purpose of the Study:

• To numerically investigate dynamic control over spontaneous emission rates using tunable HMMs.
• To explore the impact of topological transitions in HMM dispersion on emitter properties.
• To demonstrate tunability across visible, telecommunication, and mid-IR ranges.

Main Methods:

• Numerical investigation of metal-dielectric thin-film stacks.
• Incorporation of tunable materials (e.g., Sb2S3, VO2, graphene) into HMMs.
• Analysis of topological transitions from elliptical to hyperbolic dispersion.

Main Results:

• Significant tunability in Purcell enhancement and quantum efficiency observed in visible range using TiN/${{\rm Sb}_2}{{\rm S}_3}$Sb₂S₃ HMMs.
• Tunable Purcell enhancement demonstrated in telecommunication range with TiN/${{\rm VO}_2}$TiN/VO₂-HMM.
• Tunable spontaneous emission rate achieved in mid-IR using graphene/${{\rm MgF}_2}$graphene/MgF₂ HMM by modulating graphene conductivity.

Conclusions:

• Tunable HMMs provide effective dynamic control over quantum emitter spontaneous emission rates.
• The choice of materials (metal nitrides for visible/NIR, fluorides for mid-IR) is critical for achieving significant changes in effective permittivity.
• This approach offers a pathway for designing advanced quantum optical devices.