Visible to mid-infrared giant in-plane optical anisotropy in ternary van der Waals crystals

Y Feng, R Chen, J He, L Qi, Y Zhang, T Sun… - Nature …, 2023 - nature.com
Birefringence is at the heart of photonic applications. Layered van der Waals materials
inherently support considerable out-of-plane birefringence. However, funnelling light into …

Ultrafast charge carrier and exciton dynamics in an excitonic insulator probed by time-resolved photoemission spectroscopy

S Mor, M Herzog, C Monney, J Stähler - Progress in Surface Science, 2022 - Elsevier
An excitonic insulator phase is expected to arise from the spontaneous formation of electron–
hole pairs (excitons) in semiconductors where the exciton binding energy exceeds the size …

High-Gain MoS2/Ta2NiSe5 Heterojunction Photodetectors with Charge Transfer and Suppressing Dark Current

T Guo, X Song, P Wei, J Li, Y Gao… - … Applied Materials & …, 2022 - ACS Publications
Emerging two-dimensional narrow band gap materials with tunable band gaps and unique
electrical and optical properties have shown tremendous potential in broadband …

Evidence of high-temperature exciton condensation in a two-dimensional semimetal

Q Gao, Y Chan, Y Wang, H Zhang, P Jinxu… - Nature …, 2023 - nature.com
Electrons and holes can spontaneously form excitons and condense in a semimetal or
semiconductor, as predicted decades ago. This type of Bose condensation can happen at …

The spontaneous symmetry breaking in Ta2NiSe5 is structural in nature

E Baldini, A Zong, D Choi, C Lee… - Proceedings of the …, 2023 - National Acad Sciences
The excitonic insulator is an electronically driven phase of matter that emerges upon the
spontaneous formation and Bose condensation of excitons. Detecting this exotic order in …

Giant Superlinear Power Dependence of Photocurrent Based on Layered Ta2NiS5 Photodetector

X Meng, Y Du, W Wu, NB Joseph, X Deng… - Advanced …, 2023 - Wiley Online Library
Photodetector based on two‐dimensional (2D) materials is an ongoing quest in
optoelectronics. 2D photodetectors are generally efficient at low illuminating power but suffer …

Coherent Phonon Assisted Ultrafast Order-Parameter Reversal and Hidden Metallic State in

M Guan, D Chen, Q Chen, Y Yao, S Meng - Physical Review Letters, 2023 - APS
The nonequilibrium dynamics during photoinduced insulator-to-metal transition (IMT) in the
excitonic insulator (EI) candidate Ta 2 NiSe 5 have been investigated, which reproduce the …

Evidence for an Excitonic Insulator State in

J Huang, B Jiang, J Yao, D Yan, X Lei, J Gao, Z Guo… - Physical Review X, 2024 - APS
The excitonic insulator (EI) is an exotic ground state of narrow-gap semiconductors and
semimetals arising from spontaneous condensation of electron-hole pairs bound by …

High-performance flexible broadband photodetectors enabled by 2D Ta2NiSe5 nanosheets

T Guo, Z Sa, P Wei, Y Jian, X Chen, Z Chen, J Avila… - 2D …, 2023 - iopscience.iop.org
Flexible broadband optoelectronic devices play a prominent role in the areas of daily life
including wearable optoelectronic systems, health care, and bio-imaging systems. Two …

Disentangling Lattice and Electronic Instabilities in the Excitonic Insulator Candidate by Nonequilibrium Spectroscopy

K Katsumi, A Alekhin, SM Souliou, M Merz… - Physical Review Letters, 2023 - APS
Ta 2 NiSe 5 is an excitonic insulator candidate showing the semiconductor or semimetal-to-
insulator (SI) transition below T c= 326 K. However, since a structural transition …