Photo-luminescence properties of ion implanted Er3+-defects in 4H-SiCOI towards integrated quantum photonics

TL;DR

The paper addresses the challenge of realizing telecom-band, CMOS-compatible Er$^{3+}$-based quantum emitters integrated with photonic circuits. It combines ion implantation of Er$^{3+}$ into thin-film 4H-SiCOI with finite-element modeling of Purcell enhancement and comprehensive photoluminescence, lifetime, and polarization analyses. Key findings include a stable ZPL in the $1528$–$1534\ \mathrm{nm}$ range across 5 K to RT, annealing-optimized lifetimes approaching $\sim$0.8 ms, and polarization signatures consistent with $C_{3V}$ symmetry; Purcell effects are modest but geometry-dependent. The work demonstrates a scalable, CMOS-compatible Er$^{3+}$ defect platform for integrated quantum photonics with potential applications in on-chip quantum memory and telecom-band quantum networking.

Abstract

Colour centres hosted in solid-state materials such as silicon carbide and diamond are promising candidates for integration into chip-scale quantum systems. Specifically, the incorporation of these colour centres within photonic integrated circuits may enable precise control over their inherent photo-physical properties through strong light-matter interaction. Here, we investigate ion-implanted erbium ($\text{Er}^{3+}$) defects embedded in thin-film 4H-silicon-carbide-on-insulator (4H-SiCOI). Optimized implantation conditions and thermal annealing processes designed to enhance the emission characteristics of the $\text{Er}^{3+}$-defect are reported. By examining key properties such as photoluminescence intensity, optical lifetime, and polarization, we present an analysis of ensemble $\text{Er}^{3+}$-defects within 4H-SiCOI, providing insights into their potential for future quantum applications.

Figures (5)

• Figure 1: Waveguide mode, ion implantation profile and $\text{Er}^{3+}$-defect to waveguide coupling-simulation: a) schematic illustration of a photonic chip with two different sample architectures (SiC thin film and waveguide (WG)) ; b) ANSYS Lumerical FDTD $\text{TE}_{\text{00}}$-simulation of an air-cladded WG hosted in 4H-SiCOI with SLT: slap layer thickness, $\lambda$: light wavelength, BA: base angle of waveguide, H: waveguide height, $\text{n}_{\text{4H-SiC}}$: refractive index of 4H-SiC at desired wavelength, W: waveguide width, c) $\text{Er}^{3+}$ implantation profile in 4H-SiCOI (black), obtained from $\text{Er}^{3+}$ implantation at two different ion energies and fluences (green and blue). The optical mode is shown in red; d) simulated electric field from the vertical dipole-emission coupled to a WG with a top-view; e) simulated coupling efficiency of a vertical dipole radiating into a WG-structure versus depth of dipole location; f) simulated impact of the dipole-orientation within a SiCOI WG on the coupling efficiency for a dipole at 315 nm depth with schematic photon emission direction of the dipole indicated by arrows.
• Figure 2: Ion implantation and photoluminescence measurements: a) schematic illustration of the ion implantation process into 4H-SiCOI samples, b) energy level diagram of a spin-1/2 system, c) confocal-map of a $\text{Er}^{3+}$-sample at 5 K with a 200$\times$200$\mu$m scanning range and a resolution of 500 nm, d) spectrum of obtained $\text{Er}^{3+}$-defect's investigated measured at 5 K and RT with an additional measurement from unimplanted material at RT, e) study of ZPL intensity over annealing temperature, determined by integrating the obtained PL data-points between 1528 nm and 1534 nm, f) ZPL-intensity traces observed over various measurement-temperatures with data-points determined by integrating the obtained PL measurement data between 1528 nm and 1534 nm.
• Figure 3: Optical lifetime properties of observed $\text{Er}^{3+}$-defects: a) observed time-trace of an $\text{Er}^{3+}$-defect; b) Impact of annealing temperature on optical lifetime with 785 nm excitation-wavelength at RT; c) Impact of measurement temperature on optical lifetime with 785 nm excitation-wavelength.
• Figure 4: Dipole-interaction simulation within thin-film 4H-SiC or WG hosted in 4H-SiCOI: a) decay rate simulation of $\text{Er}^{3+}$-dipoles within thin-film 4H-SiC relative to bulk ($\gamma_{\infty}$); b) decay rate simulation of $\text{Er}^{3+}$-dipole within 4H-SiC waveguides relative to bulk ($\gamma_{\infty}$)
• Figure 5: Polarization properties of observed $\text{Er}^{3+}$-defects: a) observed photon absorption dipole; b) observed photon emission properties from the ensemble-defect.