相关论文: Controllable p$-$n junctions in three$-$dimensiona…
Motivated by the results of recent transport and optical conductivity studies, we propose a semi-infinite two-dimensional lattice model for interacting massive Dirac electrons in the pressurized organic conductor…
To date, endeavors in nanoscale spintronics are dominated by the use of single-electron or single-spin transistors having at their heart a semiconductor, metallic or molecular quantum dot who's localized states are non-spin-degenerate and…
Three-dimensional Dirac semimetals, a three-dimensional analogue of graphene, are unusual quantum materials with massless Dirac fermions, which can be further converted to Weyl fermions by breaking time reversal or inversion symmetry.…
We consider a junction between surface $p$-type and surface $n$-type on an ideal topological insulator in which carrier type and density in two adjacent regions are locally controlled by composition graded doping or electrical gating. Such…
We have investigated metallic break junctions of the heavy-fermion compound UPd2Al3 at low temperatures between 0.1K and 9K and in magnetic fields up to 8T. Both the current-voltage I(V) characteristics and the dV/dI (V) spectra clearly…
Modern three-dimensional nanofabrication methods make it possible to generate arbitrarily shaped nanomagnets, including periodic networks of interconnected magnetic nanowires. Structurally similar to optical or acoustic metamaterials, these…
We examined high-pressure electronic structure of a single-component molecular conductor [Pd(dddt)$_2$] (dddt = 5,6-dihydro-1,4-dithiin-2,3-dithiolate) at room temperature, based on the crystal structure determined by single crystal…
We propose a general framework for constructing a large set of nodal-point semimetals by tuning the number of linearly ($d_L$) and (at most) quadratically ($d_Q$) dispersing directions. By virtue of such a unifying scheme, we identify a new…
The current-dipole conductivity formula for doped three-dimensional Dirac semimetals is derived by using a modified gauge-invariant tight-binding approach. In a heavily doped regime, the effective number of charge carriers $n_{\alpha…
We study the properties of Dirac fermions on the surface of a topological insulator in the presence of crossed electric and magnetic fields. We provide an exact solution to this problem and demonstrate that, in contrast to their…
We measure the rectified dc currents resulting when a 3-terminal semiconductor device with gate-dependent conductance is driven with an ac gate voltage. The rectified currents exhibit surprisingly complex behaviour as the dc source-drain…
Dirac node lines (DNLs) are characterized by Dirac-type linear crossings between valence and conduction bands along one-dimensional node lines in the Brillouin zone (BZ). Spin-orbit coupling (SOC) usually shifts the degeneracy at the…
Time-reversal invariance and inversion symmetry are responsible for the topological band structure in Dirac semimetals. These symmetries can be broken by applying an external magnetic or electric field, resulting in fundamental changes to…
Spatial confinement and manipulation of charged carriers in semiconducting nanostructures are essential for realizing quantum electronic devices. Gate-defined nanostructures made of two-dimensional (2D) semiconducting transition metal…
Metal-based electronics is attractive for fast and radiation-hard electronic circuits and remains one of the longstanding goals for researchers. The emergence of 1T-TaS$_2$, a layered material exhibiting strong charge density wave (CDW)…
Gate-tunable semiconductor-superconductor nanowires with superconducting leads form exotic Josephson junctions that are a highly desirable platform for two types of qubits: those with topological superconductivity (Majorana qubits) and…
The Dirac semimetal PdTe${}_2$ becomes superconducting at a temperature $T_{c}=1.6$~K. Thermodynamic and muon spin rotation experiments support type-I superconductivity, which is unusual for a binary compound. A key property of a type-I…
We fabricate and investigate high quality graphene devices with contactless, suspended top gates, and demonstrate formation of graphene pnp junctions with tunable polarity and doping levels. The device resistance displays distinct…
Semiconductor p-n junctions are essential building blocks for modern electronics and optoelectronics. In conventional semiconductors, a p-n junction produces depletion regions of free charge carriers at equilibrium and built-in potentials…
We explore the physical properties of a unified microscopic theory for the coexistence of superconductivity and charge density waves in two-dimensional transition metal dichalcogenides. In the case of particle-hole symmetry the elementary…