Transient translation symmetry breaking via quartic-order negative light-phonon coupling at the Brillouin zone boundary in KTaO${}_3$

Abstract

KTaO${}_3$ presents a rich hyper-Raman spectrum originating from two-phonon processes at the Brillouin zone boundary, indicating the possibility of driving these phonon modes using intense midinfrared laser sources. We obtained the coupling of light to the highest-frequency longitudinal optic phonon mode $Q_{\mathrm{HY}}$ at the $X$ $(0,0,\frac{1}{2})$ point by first principles calculations of the total energy as a function of the phonon coordinate $Q_{\mathrm{HY}}$ and electric field $E$. We find that the energy curve as a function of $Q_{\mathrm{HY}}$ softens for finite values of electric field, indicating the presence of $Q_{\mathrm{HY}}^2{E}^2$ nonlinearity with negative coupling coefficient. We studied the feasibility of utilizing this nonlinearity to transiently break the translation symmetry of the material by making the $Q_{\mathrm{HY}}$ mode unstable with an intense midinfrared pump pulse. We also considered the possibility that nonlinear phonon-phonon couplings can excite the lowest-frequency phonon coordinates $Q_{\mathrm{LZ}}$ and $Q_{\mathrm{LX}}$ at $X$ when the $Q_{\mathrm{HY}}$ mode is externally driven. The nonlinear phonon-phonon couplings were also obtained from first principles via total-energy calculations as a function of the phonon coordinates, and these were used to construct the coupled classical equations of motion for the phonon coordinates in the presence of an external pump term on $Q_{\mathrm{HY}}$. We numerically solved them for a range of pump frequencies and amplitudes and found three regimes where the translation symmetry is broken: i) rectification of the lowest-frequency coordinates due to large amplitude oscillation of the $Q_{\mathrm{HY}}$ coordinate about its equilibrium position, ii) rectification of only the $Q_{\mathrm{HY}}$ coordinate without displaced oscillations of the lowest-frequency coordinates, and iii) rectification of all three coordinates.

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References in corpus (28)

• Restoring the density-gradient expansion for exchange in solids and surfaces
• Generalized gradient approximation for solids and their surfaces
• Quantum ESPRESSO toward the exascale
• Pseudopotentials for high-throughput DFT calculations
• Ultrafast switching to a stable hidden topologically protected quantum state in an electronic crystal
• Nonlinear phononics: A new ultrafast route to lattice control
• A First-Principles Approach to Insulators in Finite Electric Fields
• An effective magnetic field from optically driven phonons
• Ultrafast reversal of the ferroelectric polarization
• Theory of nonlinear phononics for coherent light-control of solids
• Light-driven ultrafast phonomagnetism
• Polarizing an antiferromagnet by optical engineering of the crystal field
• Dynamical Multiferroicity
• Ultrafast phononic switching of magnetization
• Giant effective magnetic fields from optically driven chiral phonons in 4$f$ paramagnets
• Optical Stabilization of Fluctuating High Temperature Ferromagnetism in YTiO${}_3$
• Magnetophononics: ultrafast spin control through the lattice
• Proposal for ultrafast switching of ferroelectrics using mid-infrared pulses
• Parametric amplification of optical phonons
• Proposal for midinfrared light--induced ferroelectricity in oxide paraelectrics
• Breaking Symmetry with Light: Ultra-Fast Ferroelectricity and Magnetism from Three-Phonon Coupling
• Parametric excitation of an optically silent Goldstone-like phonon mode
• Nonlinear Phononic Control and Emergent Magnetism in Mott Insulating Titanates
• Ultrafast reversal of the ferroelectric polarization by a midinfrared pulse
• Light-control of materials via nonlinear phononics
• Efficient excitation of nonlinear phonons via chirped mid-infrared pulses: induced structural phase transitions
• Phonon-driven ultrafast symmetry lowering in a Bi${}_2$Se${}_3$ crystal
• Light-induced translation symmetry breaking via nonlinear phononics

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