Complex oxide heterostructures exhibit functional electronic properties such as magnetism and superconductivity. An important step toward the use of quantum materials in real-word applications is to achieve on-demand control of their ground state. One strategy consists in applying static electric fields to the material, in the spirit of the field effect transistor. I will discuss this approach on the control of the ground state of the two-dimensional electron gas found at the LaAlO3/SrTiO3 interface [1,2,3].
Another innovative strategy is based on the use of coherent light sources. Recent developments in laser technology have made it possible to generate pulses of light in the mid infrared and THz range, indeed at intensity levels that make possible to substantially perturb the properties of a solid [4,5]. Thus, we are now in a position to control the dynamics of the low-energy excitations of complex solids and, most notably, to control their macroscopic electronic properties. This technique will be applied on NdNiO3/LaAlO3 heterostructures, where the electronic properties can be tuned by coherent vibrational excitation.
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