相关论文: Valley Phase Transition in Si MOSFETs
A spin valve represents a well-established device concept in magnetic memory technologies, whose functionality is determined by electron transmission being controlled by the relative alignment of magnetic moments of the two ferromagnetic…
The 2-D electron system (2DES) in Si metal-oxide field-effect transistors (MOSFETS) consists of two distinct electron fluids interacting with each other. We calculate the total energy as a function of the density $n$, and the spin…
Alloys with a first-order magnetic transition are central to solid-state refrigeration technology, sensors and actuators, or spintronic devices. The discontinuous nature of the transition in these materials is a consequence of the coupling…
The metal-insulator transition observed in the In/Si(111)-4x1 reconstruction is studied by means of ab initio calculations of a simplified model of the surface. Different surface bands are identified and classified according to their origin…
Quantum oscillations of response functions in high magnetic fields tend to reveal some of the most interesting properties of metals. In particular, the oscillation phase shift is sensitive to topological band features, thereby helping to…
Quantum phase transitions encompass a variety of phenomena that occur in quantum systems exhibiting several possible symmetries. Traditionally, these transitions are explored by continuously varying a control parameter that connects two…
Valleytronics targets the exploitation of the additional degrees of freedom in materials where the energy of the carriers may assume several equal minimum values (valleys) at non-equivalent points of the reciprocal space. In single layers…
Silicon spin qubits are marred by the valley degeneracy of the conduction band. In a nanodevice, the degeneracy is lifted by interfaces and alloy disorder, but the arising valley splitting is small, of order 100 $\mu$eV in Si/SiGe quantum…
We discuss the choice and implementation of inter-valley potentials in the so-called two bands $\mathbf{k}\cdot\mathbf{p}$ model for the opposite $X$, $Y$ or $Z$ valleys of silicon. We focus on the description of valley splittings in…
Superconductor-to-metal transition with magnetic field and gate-voltage is studied in a Josephson junction array comprising of randomly distributed lead islands on exfoliated single-layer graphene with a back-gate. The low magnetic-field…
Using large scale Monte Carlo simulations on a uniformly frustrated 3DXY model, we report a first order vortex lattice melting transition in clean, isotropic extreme type-II $\kappa \to \infty$ superconductors. This work clarifies an…
This paper presents a conceptual approach to phase modulation of the cavity field in storage ring RF systems. An implementation of the concept on Dimtel low-level RF controllers is also presented. The method is illustrated with the test…
Most common types of symmetry breaking in quasi-one-dimensional electronic systems possess a combined manifold of states degenerate with respect to both the phase $\theta$ and the amplitude $A$ sign of the order parameter $A\exp(i\theta)$.…
A numerical study of domain wall relocation during voltage switching with different ramping times is presented for weakly coupled, doped semiconductor superlattices exhibiting multistable domain formation in the first plateau of their…
We have investigated the valley degeneracy of MoS2 multilayers and its effect on thermoelectric properties. By modulating the layer thickness and external electric field, the hole valleys at {\Gamma} and K points in the highest energy…
This study employs advanced phase-field modeling to investigate Si-based qubit MOSFETs, integrating electrostatics and quantum mechanical effects. We adopt a comprehensive modeling approach, utilizing full-wave treatment of the Schrodinger…
Nonvolatile photonic integrated circuits employing phase change materials have relied either on optical switching mechanisms with precise multi-level control but poor scalability or electrical switching with seamless integration and…
Silicon undergoes a phase transition from the semiconducting diamond phase to the metallic beta-Sn phase under pressure. We use quantum Monte Carlo calculations to predict the transformation pressure and compare the results to density…
We show that there can be no direct first order transition between a Fermi liquid and an insulating electronic (Wigner) crystalline phase in a clean two-dimensional electron gas in a metal-oxide-semiconductor field-effect transistor…
Much of the dramatic growth in research on topological materials has focused on topologically protected surface states. While the domain walls of topological materials such as Weyl semimetals with broken inversion or time-reversal symmetry…