On examining the stability of a Wigner crystal in an ionic dielectric, two competitive effects due to the polaron formation are found to be important: (i) the screening of the Coulomb force 1/εsr, which destabilizes the crystal, compensated by (ii) the increase of the carrier mass (polaron mass). The competition between the two effects is carefully studied, and the quantum melting of the polaro...

Low-dimensional perovskites offer a rare opportunity to investigate lattice dynamics and charge carrier behavior in bulk quantum-confined solids, in addition to them being the leading materials in optoelectronic applications. In particular, zero-dimensional (0D) inorganic perovskites of the Cs4PbX6 (X = Cl, Br, or I) kind have crystal structures with isolated lead halide octahedra [PbX6]4- surr...

Measurements of conductivity and thermopower as a function of oxygen fugacity (fO2) are used to derive a model for conduction in olivine. Thermopower at 1000– 1200◦C is between 50 and 400 μV/K and has a positive fO2 dependence, and electrical conductivity exhibits approximately a /11 power dependence on fO2 . However, small polarons, considered to be the conducting defect in olivine at these te...

The motion of an electron in a polar crystal has often been treated in a number of previous works motivated by its increasing interest in transport phenomena in semiconductors, which play an important role in the miniaturization of electronic devices. In addition to its possible connection with the real behavior of an electron and a crystal, this model represents one of the simplest examples of...

Recently, much effort has been devoted to improve the efficiency of organic photovoltaic solar cells based on blends of donors and acceptors molecules in bulk heterojunction architecture. One of the major losses in organic photovoltaic devices has been recombination of polaron pairs at the donor-acceptor domain interfaces. Here, we present a novel method to suppress polaron pair recombination a...

Given the emerging role of oxide spinels as hole conductors, we discuss in this article the traditional vs. new methodologies of determining the type of conduction mechanism at play––localized polaronic vs. band-like transport. Applying (i) traditional small polaron analysis to our in-situ high temperature fourpoint conductivity and thermopower measurements, we previously found an activated mob...

Lead halide perovskites show marked defect tolerance responsible for their excellent optoelectronic properties. These properties might be explained by the formation of large polarons, but how they are formed and whether organic cations are essential remain open questions. We provide a direct time domain view of large polaron formation in single-crystal lead bromide perovskites CH3NH3PbBr3 and C...

After a general introduction into the Shockley theory of current voltage (J-V) characteristics of inorganic and organic semiconductor junctions of different bandwidth, we apply the Shockley theory-based, one diode model to a new type of perovskite junctions with polaronic charge carriers. In particular, we studied manganite-titanate p-n heterojunctions made of n-doped SrTi1- y Nb y O3, y = 0.00...

Circularly polarized emission from helical MOPV4 aggregates is studied theoretically based on a Hamiltonian including excitonic coupling, exciton phonon coupling, and site disorder. The latter is modeled via a Gaussian distribution of site energies. The frequency dependence of the circularly polarized luminescence dissymmetry g(lum)(omega) contains structural information about the low-energy-ne...