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The phonon-limited electron mobility in inversion layers is studied in fully depleted silicon-on-insulator (FD-SOI) MOSFET as a function of transverse effective field and semiconductor film thickness. A quantum-mechanical procedure based on the solution of 1D-coupled Poisson/Schrödinger equations is employed to calculate the phonon-electron mobility using a relaxation time approximation. The influence of quantization effects on the phonon-limited electron mobility in ultrathin SOI, strained-SOI and GeOI MOSFET is investigated. A comparative study of mobility shows an enhancement factor varying from 1.5 to 2.5 for film thicknesses ranging from 5 nm to 20 nm using both strained-silicon and germanium materials.

The determination of pulsation mode and distance for field Cepheids is a complicated problem best resolved by a luminosity estimate. For illustration a technique based on spectroscopic luminosity discrimination is applied to the 4.47 day s-Cepheid FF Aql. Line ratios in high dispersion spectra of the variable yield values of M V = −3.40 ± 0.02 s.e. (±0.04 s.d.), average effective temperature T eff = 6195 ± 24 K, and intrinsic color ( B − V ) 0 = +0.506±0.007, corresponding to a reddening of E B−V = 0.25 ± 0.01, or E B−V (B0) = 0.26 ± 0.01. The skewed light curve, intrinsic color, and luminosity of FF Aql are consistent with fundamental mode pulsation for a small-amplitude classical Cepheid on the blue side of the instability strip, not a sinusoidal pulsator. A distance of 413 ± 14 pc is estimated from the Cepheid's angular diameter in conjunction with a mean radius of R = 39.0 ± 0.7 R inferred from its luminosity and effective temperature. The dust extinction toward FF Aql is described by a ratio of total-to-selective extinction of R V = A V /E(B − V ) = 3.16 ± 0.34 according to the star's apparent distance modulus.

We calculate numerically the exact relaxation spectrum of the totally asymmetric simple exclusion process (TASEP) with open boundary conditions on lattices up to 16 sites. In the low-and high-density phases and along the nonequilibrium first-order phase transition between these phases, but sufficiently far away from the second-order phase transition into the maximalcurrent phase, the low-lying spectrum (corresponding to the longest relaxation times) agrees well with the spectrum of a biased random walker confined to a finite lattice of the same size. The hopping rates of this random walk are given by the hopping rates of a shock (a domain wall separating stationary low-and high-density regions), which are calculated in the framework of a recently developed non-equilibrium version of Zel'dovich's theory of the kinetics of first-order transitions. We conclude that the description of the domain wall motion in the TASEP in terms of this theory of boundary-induced phase transitions is meaningful for very small systems of the order of ten lattice sites.

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