Photovoltaic effect and photopolarization in Pb[(Mg1/3Nb2/3)0.68Ti0.32]O3 crystal

TL;DR

This paper reports the discovery of a photovoltaic effect in undoped Pb[(Mg1/3Nb2/3)0.68Ti0.32]O3 crystal, showing enhanced response near ferroelectric reorientation and Curie temperature, with potential for optoelectronic applications.

Contribution

It presents the first observation of photovoltaic effects in this specific ferroelectric crystal and demonstrates significant response improvements under electric fields and temperature control.

Findings

Photovoltaic effect peaks near ferroelectric dipole reorientation.

Photovoltaic response increases threefold near the Curie temperature.

Remanent and transient photovoltaic effects are observed at ferroelectric saturation.

Abstract

Ferroelectric photovoltaic materials are an alternative to semiconductor-based photovoltaics and offer the advantage of above bandgap photovoltage generation. However, there are few known compounds, and photovoltaic efficiencies remain low. Here, we report the discovery of a photovoltaic effect in undoped lead magnesium niobate-lead titanate crystal and a significant improvement in the photovoltaic response under suitable electric fields and temperatures. The photovoltaic effect is maximum near the electric-field-driven ferroelectric dipole reorientation, and increases threefold near the Curie temperature. Moreover, at ferroelectric saturation, the photovoltaic response exhibits clear remanent and transient effects. The transient-remanent combinations together with electric and thermal tuning possibilities indicate photoferroelectric crystals as emerging elements for photovoltaics and optoelectronics, relevant to all-optical information storage and beyond.