Related papers: Bulk Photovoltaic Effect in Two-Dimensional Distor…
Piezoelectricity appears in the inversion asymmetric crystal that converts mechanical deformational force to electricity. Two-dimensional transition metal dichalcolgenide (TMDC) monolayers exhibit the piezoelectric effect due to the…
Modern electronic devices heavily rely on the accurate control of charge and spin of electrons. The emergence of controllable valley degree of freedom brings new possibilities and presents a promising prospect towards valleytronics.…
We identify a strong photovoltaic response due to the non-linear optical transition between heavy and light hole sub-bands enabled by T_d-symmetry in a quantum well, which we term the quadrupolar photovoltaic effect (QPE). The photovoltaic…
Light-to-electricity conversion is crucial for energy harvesting and photodetection, requesting efficient electron-hole pair separation to prevent recombination. Traditional junction-based mechanisms using built-in electric fields fail in…
The ultrafast photoinduced insulator-metal transition in VO2 is studied at different temperatures and excitation fluences using multi-THz probe pulses. The spectrally resolved mid-infrared response allows us to trace separately the dynamics…
A 2-D photonic crystal was integrated experimentally into a thin-film crystalline-silicon solar cell of 1-{\mu}m thickness, after numerical optimization maximizing light absorption in the active material. The photonic crystal boosted the…
Atomically thin transition metal dichalcogenides have emerged as promising candidates for sensitive photodetection. Here, we report a photoconductivity study of biased mono- and bilayer molybdenum disulfide field-effect transistors. We…
To advance knowledge of K bonding in Cu(In,Ga)(Se,S)2 (CIGS) photovoltaic (PV) absorbers, recent Cu-K-In-Se phase growth studies have been extended to PV performance. First, the effect of distributing K throughout bulk Cu1-xKxInSe2…
Quantum systems in confined geometries are host to novel physical phenomena. Examples include quantum Hall systems in semiconductors and Dirac electrons in graphene. Interest in such systems has also been intensified by the recent discovery…
We use a first-principles density functional theory approach to calculate the shift current and linear absorption of uniformly illuminated single-layer Ge and Sn monochalcogenides. We predict strong absorption in the visible spectrum and a…
Two-dimensional material (2DM)-based field-effect transistors (FETs), such as molybdenum disulfide (MoS${_2}$)-FETs, have gained significant attention for their potential for ultra-short channels, thereby extending Moore's law. However,…
We demonstrate a novel type of solar cell, one that uses fixed negative charges, formed at the interface of n-Si with Al2O3, to generate strong inversion at the Si surface by electrostatic repulsion. Built-in voltages of up to 755 mV are…
Understanding the fundamental mechanisms ruling laser-induced coherent charge transfer in hybrid organic/inorganic interfaces is of paramount importance to exploit these systems in next-generation opto-electronic applications. In a…
Kinetic of a reversible structural transition between insulating (2H) and metallic (1T') phases in a monolayer MoTe2 due to an electrostatic doping is studied using first-principle calculations. The driving force for the structural…
We study the photoresponse of single-layer MoS2 field-effect transistors by scanning photocurrent microscopy. We find that, unlike in many other semiconductors, the photocurrent generation in single-layer MoS2 is dominated by the…
We theoretically revealed that a weak photoexcitation achieves the electric polarization-inversion with approximately $18\%$ of all the charges, which was interpreted as a superimposition of multi-exciton states, from the charge-ordered…
Ternary chalcostibite copper antimony selenide (CuSbSe2) is a promising absorber material for next generation thin film solar cells due to the non-toxic nature, earth-abundance, low-cost fabrication technique, optimum bandgap and high…
We investigated poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl-C61 butyric acid methyl ester bulk heterojunction (BHJ) solar cells by means of pulsed photocurrent, temperature dependent current-voltage and capacitance-voltage measurements. We…
We have made a detailed temperature-dependent photoemission study of VO_2/TiO_2(001) thin films, which show a metal-insulator transition at \sim 300 K. Clean surfaces were obtained by annealing the films in an oxygen atmosphere. Spectral…
We have investigated the effect of potassium (K) intercalation on $2H$-MoS$_2$ using transmission electron energy-loss spectroscopy. For K concentrations up to approximately 0.4, the crystals appear to be inhomogeneous with a mix of…