Terahertz-driven ultrafast dynamics of rare-earth nickelates by controlling only the charge degree of freedom

Abstract

An important strategy for understanding the microscopic physics of strongly correlated systems and enhancing their technological potential is to selectively drive the fundamental degrees of freedom out of equilibrium. Intense terahertz (THz) pulses with photon energies of a few meV, can not only serve this purpose but also unravel their electronic and quantum nature. Here, we present THz-driven ultrafast dynamics of rare-earth nickelates ${\text{RNiO}}_{\text{3}}$, $\text{R}$ = rare-earth atom) - a prototype system to study the Mott insulator-metal transition (IMT). The THz drive of its Mott insulating state induces instantaneous IMT via quantum tunneling of valence electrons across the bandgap while the THz drive of its correlated metallic state leads to overall heating of the conduction electrons. The subsequent relaxations of excited electrons in these two states occur via a two-step process (electron-phonon thermalization and recovery of the charge-ordered insulating state) and a one-step process (electron-phonon scattering), respectively. The relaxation dynamics of the electrons and the absence of acoustic phonon modes, in particular, suggest that the THz photons drive only the charge degree of freedom. The purely electronic, ultrafast and local nature of the THz-induced IMT offers its applications in opto-electronics with enhanced performance and minimal device size and heat dissipation.

References in corpus (20)

• Memory Metamaterials
• Terahertz-Field-Induced Ferroelectricity in Quantum Paraelectric SrTiO${}_3$
• Site-selective Mott transition in rare earth nickelates
• Charge disproportionation without charge transfer in the rare-earth nickelates as a possible mechanism for the metal-insulator transition
• Ultrafast strain engineering in complex oxide heterostructures
• Bond disproportionation and dynamical charge fluctuations in the perovskite rare earth nickelates
• How optical excitation controls the structure and properties of vanadium dioxide
• Spatially resolved ultrafast magnetic dynamics launched at a complex-oxide hetero-interface
• Non-perturbative high-harmonic generation in the three-dimensional Dirac semimetal Cd${}_3$As${}_2$
• Direct Observation of Decoupled Structural and Electronic Transitions and an Ambient Pressure Monoclinic-Like Metallic Phase of VO${}_2$
• Non-linear doublon production in a Mott insulator --- Landau-Dykhne method applied to an integrable model
• Landau theory of charge and spin ordering in the nickelates
• A heterojunction modulation-doped Mott transistor
• Antiferromagnetic metal phase in an electron-doped rare-earth nickelate
• Multiple supersonic phase fronts launched at a complex-oxide hetero-interface
• Observation and Structural Control of Charge-Density-Waves resonating with Terahertz Frequencies in NdNiO3
• Broadband THz spectroscopy of the insulator-metal transition driven by coherent lattice deformation at the SmNiO3/LaAlO3 interface
• Probing photo-induced rearrangements in the NdNiO${}_3$ magnetic spiral with polarization-sensitive ultrafast resonant soft x-ray scattering
• Probing the evolution of electronic phase-coexistence in complex systems by terahertz radiation
• Terahertz harmonic generation across the Mott insulator-metal transition

Cited by in corpus (1)

• Terahertz harmonic generation across the Mott insulator-metal transition