Modulating Nonlinear Optical Properties of (1R,2R)-DACHGeI₄ through Ce³⁺ Doping

Area of Science:

• Materials Science
• Solid-State Physics
• Quantum Optics

Background:

• Chiral perovskites are promising for polarization optics and spintronics.
• Germanium-based perovskites offer unique electronic and structural properties.
• Lattice defects can negatively impact the optical performance of germanium perovskites.

Purpose of the Study:

• To synthesize a novel 2D germanium-based chiral perovskite, (1R,2R)-DACHGeI4.
• To investigate the effects of Ce3+ doping on the structural and optical properties.
• To explore the relationship between chirality and spintronic states in germanium perovskites.

Main Methods:

• Synthesis of (1R,2R)-DACHGeI4 single crystals using (1R,2R)-DACH.
• Incorporation of rare-earth Ce3+ as a dopant for defect compensation.
• Experimental characterization including photoluminescence and structural analysis.
• Density Functional Theory (DFT) calculations for theoretical validation.

Main Results:

• Ce3+ doping improved photoluminescence quantum yield and fluorescence lifetime.
• Doping regulated spintronic states and induced lattice distortion by substituting Ge2+.
• The crystal structure transitioned from chiral P21212 to nonchiral Pba2, eliminating chirality.
• DFT calculations corroborated the experimental findings on structural and electronic changes.

Conclusions:

• Ce3+ doping is an effective strategy to enhance optical properties and tune spintronic states in 2D germanium perovskites.
• The study demonstrates that doping can intentionally destroy chirality, impacting crystal symmetry and properties.
• This work provides a new avenue for optimizing nonlinear optical applications and understanding chiral perovskite spintronics.