Our Vision

The Kirmani Group is exploring a complementary design principle for extreme-environment optoelectronics: a semiconductor may remain functional not only because it resists defect formation, but also because it can rapidly reorganize, neutralize, or remove the defects that form.

This possibility is especially relevant to metal-halide perovskites (MHPs) and other structurally dynamic semiconductors. Their soft, polar, anharmonic, and partially ionic lattices can support structural rearrangement over a wide range of length and time scales. These characteristics are frequently treated as sources of instability, but they may also provide pathways for defect migration, recombination, and electronic passivation.

Radiation response in these materials therefore cannot be described by damage generation alone. It emerges from competition among:

• the rate at which radiation creates defects;
• the spatial distribution of deposited energy;
• the rate at which defects migrate or recombine;
• the influence of temperature, illumination, and electrical bias;
• the response of interfaces and transport layers; and
• the accumulation of irreversible chemical or structural changes.

Our research seeks to quantify this competition and determine the boundaries separating recoverable damage, steady-state defect populations, and irreversible failure.

We combine controlled irradiation, cryogenic experiments, operando electrical measurements, defect spectroscopy, optical and structural characterization, and multiscale modeling. These approaches connect fundamental energy-deposition events to defect kinetics and ultimately to the performance of complete devices.

The resulting knowledge will support a new generation of lightweight, printable, and radiation-resilient photovoltaics, sensors, and electronic materials for orbital, deep-space, nuclear, and other extreme environments.