Nonlinear microscopy of lead iodide nanosheets

Area of Science:

• Materials Science
• Optoelectronics
• Nanoscience

Background:

• Lead iodide (PbI2) is a van der Waals layered semiconductor with a direct bandgap.
• PbI2 nanosheets show promise for optoelectronic devices but their optical properties are underexplored.
• PbI2 is a key precursor for perovskite materials.

Purpose of the Study:

• To determine the nonlinear optical properties of PbI2 nanosheets.
• To investigate factors influencing these nonlinear optical properties.
• To explore the potential of PbI2 nanosheets as nonlinear and quantum light sources.

Main Methods:

• Utilized nonlinear microscopy as a non-invasive optical technique.
• Investigated PbI2 nanosheets with varying crystalline orientation, thickness, and substrate influence.
• Quantified nonlinear optical properties, including second- and third-order nonlinear susceptibilities.

Main Results:

• Demonstrated nonlinearity enhancement dependent on excitonic resonances.
• Observed influence of crystalline orientation, thickness, and substrate on nonlinear optical response.
• Successfully estimated second- and third-order nonlinear susceptibilities of PbI2 nanosheets.

Conclusions:

• Nonlinear optical properties of PbI2 nanosheets are significant and tunable.
• These findings open new avenues for utilizing PbI2 nanosheets in advanced optical applications.
• PbI2 nanosheets are promising candidates for novel nonlinear and quantum light sources.