Research



The objective of our lab is to study the basic properties of functional soft-semiconductors, and to develop different applicative devices based on these studies. In the lab we combine Chemistry, Physics and Materials science to gain full understanding of the materials’ characteristics and potential.

The work in the lab begins with the design and synthesis of the compounds and a basic characterization to understand their structure and physical properties. Compounds with relevant characteristics are studied using advanced microscopy and spectroscopy to study fundamental physical processes and specifically light-matter interactions and structural dynamics. Utilizing this knowledge, we design and fabricate electro-optical devices such as high-energy (X-Ray) detectors and light emitting diodes (LED) based on these compounds.

 

Design and Synthesis of Soft-Semiconductors

Soft-semiconductors such as halide-perovskites can be synthesized by simple wet chemistry methods, allowing a cheap and scalable fabrication of efficient devices based on these compounds. We aim to gain improved understanding and synthetic control over their composition, structure, size and dimensionality in order to study the structure-functionality in these compounds. Such control will allow a rational design of materials for various applications. We utilize various synthesis and crystal growth techniques, to obtain various samples from large single-crystals to poly-crystalline powder and colloidal nano-crystals, depending on the exact study. Upon synthesis we use structural characterization based on X-ray diffraction to resolve the crystal structure and optical spectroscopy (absorption and photoluminescence) to classify these materials for specific applications. 

Perovskite crystal structure

Light-Matter Interactions in Soft-Semiconductors

Soft-semiconductors, such as halide perovskites, are functional materials with dynamic crystal lattice that enables strong interactions between the atoms, charge carriers (electrons), and electromagnetic radiation (light).
In the lab we are developing a unique microscopy/spectroscopy setup that will allow us to study these materials under various excitations from visible light and up to high-energy X-ray radiation.
The hypothesis is that in soft-semiconductors, the different excitations will modify the physical and structural dynamics, unlike traditional semiconductors, and will allow us to gain deeper understanding regarding the fundamental light-matter interactions in these unique materials.

Photoluminesence microscopy

Development of X-Ray Detectors

Based on the properties of these materials we will fabricate and study detectors for high-energy X-ray photons that can be integrated in various modern applications for medical diagnostics, industrial inspection and homeland security. We will focus on two types of detectors –

A. Direct semiconductor detector, in which the charges forming upon interaction with X-ray photon are collected directly, allowing high sensitivity and energy resolution.

B. Scintillator based detectors in which the impact of the X-ray photon leads to the emission of scintillated photons that can be collected optically. These detectors enable rapid detection  crucial for modern medical scanning devices.

These detectors will be studied both to understand fundamental processes that occurs upon impact of X-ray photon and in applicative aspect to improve their properties for the needs of the specific applications.

Perovskite detector

Development of Light Emitting Devices

Energy efficient light emitting devices are a crucial component for modern days, required for applications spanning from high-end displays to simple illumination. We will explore the utilization halide-perovskite for different light emission applications, each with unique set of requirements. The ability to control the materials’ properties by modifying the composition, structure, size and dimensionality will be harnessed to tune them for the following applications -

A. Broadband halide-perovskites with ‘white-light’ illumination will be studied for simple, cost effective and energy efficient illumination application, to replace current LED light bulbs  based on color conversion films.

B. Low-dimensional halide-perovskites with controlled color and fast decay dynamics will be utilized to develop LED with fast response and broad color-gamut for advanced display applications.

Single crystal photoluminesence