Jonathan E Spanier

The present disclosure is directed to using MXene compositions as templates for the deposition of oriented perovskite films, and compositions derived from such methods. Certain specific embodiments include methods preparing an oriented perovskite, perovskite-type, or perovskite-like film, the methods comprising: (a) depositing at least one perovskite, perovskite-type, or perovskite-like composition or precursor composition using chemical vapor deposition (CVD), physical vapor deposition (PVD), or atomic layer deposition (ALD) onto a film or layer of a MXene composition supported on a substrate to form a layered composition or precursor composition; and either (b) (1) heat treating or annealing the layered precursor composition to form a layered perovskite-type structure comprising at least one oriented perovskite, perovskite-type, or perovskite-like composition; or (2) annealing the layered composition; or (3) both (1) and (2).

Coupling of switchable ferroelectric polarization with the carrier transport in an adjacent semiconductor enables a robust, non-volatile manipulation of the conductance in a host of low-dimensional systems, including the two-dimensional electron liquid that forms at the LaAlO3-SrTiO3 interface. However, the strength of the gate-channel coupling is relatively weak, limited in part by the electrostatic potential difference across a ferroelectric gate. Compositionally grading of PbZr1-xTixO3 ferroelectric gates enables a more than twenty-five-fold increase in the LAO/STO channel conductance on/off ratios. Incorporation of polarization gradients in ferroelectric gates can enable significantly enhanced performance of ferroelectric non-volatile memories.

Metal-semiconductor-metal (MSM) photodetectors may see increased responsivity when a plasmonic lens is integrated with the photodetector. The increased responsivity of the photodetector may be a result of effectively 'guiding' photons into the active area of the device in the form of a surface plasmon polariton. In one embodiment, the plasmonic lens may not substantially decrease the speed of the MSM photodetector. In another embodiment, the Shottkey contacts of the MSM photodetector may be corrugated to provide integrated plasmonic lens. For example, one or more of the cathodes and anodes can be modified to create a plurality of corrugations. These corrugations may be configured as a plasmonic lens on the surface of a photodetector. The corrugations may be configured as parallel linear corrugations, equally spaced curved corrugations, curved parallel corrugations, approximately equally spaced concentric circular corrugations, chirped corrugations or the like.