Coupled pyroelectric-photovoltaic effect in 2D ferroelectric $α$-In$_2$Se$_3$

Michael Uzhansky; Abhishek Rakshit; Yoav Kalcheim; Elad Koren

Home/Archive/arXiv

arXiv · 2312.17360

Coupled pyroelectric-photovoltaic effect in 2D ferroelectric $α$-In$_2$Se$_3$

Michael Uzhansky·Abhishek Rakshit·Yoav Kalcheim·Elad Koren

View original source ↗Read source document ↗Export metadata ↓

Abstract

Pyroelectric and photovoltaic effects are vital in cutting-edge thermal imaging, infrared sensors, thermal and solar energy harvesting. Recent advances revealed the great potential of the bulk photovoltaic effect in two-dimensional (2D) semiconductor-ferroelectric materials to enable reconfigurable p-n junction operation with the potential to surpass the Shockley-Queiseer limit. Moreover, the extremely low thickness, high thermal conductivity, dangling bonds free interface, and room-temperature stable ferroelectricity down to a single monolayer endow 2D ferroelectrics with a superior pyroelectric figure of merit. Herein, we performed direct pyroelectric measurements of 2D $α$-In$_2$Se$_3$ under dark and light conditions. The results reveal a gigantic pyroelectric coefficient of 30.7 mC/m$^2$K and a figure of merit of 135.9 m$^2$/C. In addition, we perform temperature-dependent short-circuit photovoltaic response measurements in which the excess photocurrent is modulated in proportion with the temperature variations due to the induced in-plane potential variations. Consequently, the discovered pyroelectric-photovoltaic effect allows the combination of direct temperature (photovoltaic) and temperature-derivative (pyroelectric) sensing. Finally, we utilized the intercoupled ferroelectricity of In$_2$Se$_3$ to realize a non-volatile, self-powered photovoltaic memory operation, demonstrating a stable short-circuit current switching with a decent 103 ON-OFF ratio. The coupled pyroelectric-photovoltaic effect, along with reconfigurable photocurrent, pave the way for a novel monolithic device technology with integrated thermal and optical response, in-memory logic and energy harvesting.

Explore related subjects

physics.app-ph cond-mat.mes-hall

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Michael Uzhansky, Abhishek Rakshit, Yoav Kalcheim, Elad Koren. 2023-12-28. Coupled pyroelectric-photovoltaic effect in 2D ferroelectric $α$-In$_2$Se$_3$. https://arxiv.org/abs/2312.17360

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Janus Dipoles: Fundamentals, Realizations, and Emerging Applications

The Janus dipole - featuring orthogonally oriented electric and magnetic dipoles with a 90-degree phase difference - has emerged as a powerful paradigm for wave manipulation. Unlike traditional Huygens dipoles used for directional control, this unique configuration exhibits strongly asymmetric, face-selective near-field behavior while maintaining a quasi-isotropic far-field radiation pattern. These remarkable properties make the Janus dipole an essential platform for directional wave shaping, with wide-ranging applications in on-chip photonics, quantum interactions, and wireless power transfer. This review systematically traces the rapid development of the Janus dipole from its foundational theoretical inception to its diverse implementation platforms across optical, microwave, and acoustic frequencies. In this paper, we explore the governing principles, classify realization strategies into passive Janus dipoles, active Janus dipoles, and advanced near-field coupling control, and highlight emerging frontiers. By bridging foundational electrodynamics with advanced device engineering, this paper serves as an essential reference and roadmap for researchers designing next-generation, highly integrated, and compact wave-manipulation systems.

physics.app-ph↗

arXiv2026

Evaluation of effective wave velocities in polycrystalline materials using the ultrasonic reflection matrix

In-depth characterization of heterogeneous materials has long been a challenge in non-destructive testing. Here, a method is proposed to determine the elastic constants of metallic polycrystalline materials using back-scattered ultrasound. The waves scattered by the microstructure are analyzed to image the effective bulk velocities. To this end, a reflection matrix is acquired with an array of transducers. The projection of this matrix onto a focused basis is used to estimate an average point spread function. Optimizing this function with respect to the propagation model leads to an estimation of the longitudinal velocity. Additional treatments are developed to adapt the method to map the shear wave velocity. The local Poisson's ratio is then deduced from the ratio between those two velocities. Young's modulus and shear modulus can also be obtained assuming known densities. This matrix approach is experimentally validated on different polycrystalline materials. A sample displaying heterogeneous mechanical properties is then simulated to assess the accuracy and the resolution of the method. Its strengths and limitations are discussed, demonstrating its potential for quantitative non-destructive material characterization.

physics.app-ph↗

arXiv2026

Pendellösung length-scale neutron and X-ray interferometry

Neutron and X-ray perfect-crystal interferometers (PCIs) are powerful platforms for studies of fundamental physics and phase-contrast imaging. Further enhancing several PCI capabilities requires reducing crystal blade thickness to the micron scale, which minimizes dynamical-diffraction image blur, permits operation in the pendellösung regime where blade thickness controls beam splitting, and reduces absorption for simultaneous neutron and X-ray operation. However, fabricating multiple crystal blades with identical micrometer-scale thicknesses over centimeter-scale areas remains a major challenge. Here, using a non-etching sub-micron fabrication technique, we demonstrate silicon triple-Laue interferometers with equal-blade-thicknesses of 110 $μ$m and 350 $μ$m, operated with both neutrons and X-rays. These devices are the thinnest PCIs realized to date, enabling a factor-of-six reduction in dynamical-diffraction beam spreading for improved phase-contrast imaging, while reaching the single pendellösung length regime in which crystal thickness provides an experimentally accessible control parameter for engineered quantum-optical beam splitting of plane-wave inputs. These results motivate multi-blade PCI designs utilizing identical half-pendellösung crystal lamellae that are proposed for neutron spin--orbit and electric dipole moment measurements.

physics.app-ph↗