Dielectric properties of cubic boron nitride modulated by an ultrashort laser pulse

The transient dielectric responses of cubic boron nitride (cBN) modulated by an ultrashort laser pulse are introduced based on time-dependent density functional theory calculations. We theoretically investigate whether an ultrashort laser pulse is able to reversibly drive the electric and optical properties of cBN to change profoundly without damage. With easily tunable laser parameters, the cBN can even be switched by reversal of both elliptic and hyperbolic behaviors for a particular working frequency window. We describe the evolution of the transient dielectric function throughout the duration of the pulse, which can exhibit a reversible behavior driven by the instantaneous optical field for a purposely designed laser pulse, providing a fundamental possibility for applications of all-optical signal processing and optical-field-effect devices.