Terahertz-driven Local Dipolar Correlation in a Quantum Paraelectric

Abstract

Light-induced ferroelectricity in quantum paraelectrics is a new avenue of achieving dynamic stabilization of hidden orders in quantum materials. In this work, we explore the possibility of driving transient ferroelectric phase in the quantum paraelectric KTaO${}_3$ via intense THz excitation of the soft mode. We observe a long-lived relaxation in the THz-driven second harmonic generation signal (SHG) that lasts up to 20 ps at 10 K which may be attributed to light-induced ferroelectricity. Through analyzing the THz-induced coherent soft-mode oscillation and finding its hardening with fluence well described by a single well potential, we demonstrate intense THz pulses up to 500 kV/cm cannot drive a global ferroelectric phase in KTaO${}_3$. Instead, we find the unusual long-lived relaxation of SHG comes from a THz-driven moderate dipolar correlation between the defect-induced local polar structures. We discuss the impact of our findings on current investigations of the THz-induced ferroelectric phase in quantum paraelectrics.

arXiv commentAccepted for publication in Physical Review Letters

References in corpus (6)

• Terahertz-Field-Induced Ferroelectricity in Quantum Paraelectric SrTiO${}_3$
• Metastable ferroelectricity in optically strained $SrTi{O}_3$
• Ultrafast reversal of the ferroelectric polarization
• Proposal for midinfrared light--induced ferroelectricity in oxide paraelectrics
• The quantum paraelectric phase of SrTiO${}_3$ from first principles
• Simulating terahertz field-induced ferroelectricity in quantum paraelectric SrTiO${}_3$

Cited by in corpus (6)

• Quantum fluctuations lead to glassy electron dynamics in the good metal regime of electron doped KTaO3
• Time-domain study of coupled collective excitations in quantum materials
• Tunable Spatiotemporal Orders in Driven Insulators
• Anharmonic coherent dynamics of the soft phonon mode of a PbTe crystal
• Theory of terahertz pulse transmission through ferroelectric nanomembranes
• Terahertz-induced tunnel ionization drives coherent Raman-active phonon in Bismuth