Test structure design for the evaluation of carrier-carrierscattering effect on hole and electron mobilities

In this paper we present a new three-terminal test structure that enables one to simply evaluate the reduction in the hole and electron mobilities due to the carrier-carrier scattering effect. The use of a three-terminal device is necessary to remove the limitations of other measurement methods and to separately obtain μ_n and μ _p. An investigation of the role of the geometrical parameters of the test structure highlights its suitability and flexibility for the mobility extraction procedure. Numerical simulation is used to carefully design the test structure and to verify the accuracy of the measurement method. Experimental results obtained from n-type silicon regions are presented and compared to major analytical models     

Effect of niobium additions on the structure and magnetic properties of equiatomic iron-cobalt alloys

The structure of equiatomic iron-cobalt alloys containing 1, 2 and 3 wt% niobium has been studied using a variety of techniques, including X-ray diffraction, scanning and transmission electron microscopy and differential thermal analysis. It has been found that niobium is effective in reducing the kinetics of ordering to the B2 structure and of anti-phase domain growth, even though the solubility is only 0.3–0.5 wt%. The magnetic properties (coercive force and saturation magnetization) and the electrical resistivity of the three alloys have also been determined.     

Edge coloring of bipartite graphs with constraints

A classical result from graph theory states that the edges of an l-regular bipartite graph can be colored using exactly l colors so that edges that share an endpoint are assigned different colors. In this paper, we study two constrained versions of the bipartite edge coloring problem.

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The power of verification for one-parameter agents

We initiate the study of mechanisms with verification for one-parameter agents. We give an algorithmic characterization of such mechanisms and show that they are provably better than mechanisms without verification, i.e., those previously considered in the literature. These results are obtained for a number of optimization problems motivated by the Internet and recently studied in the algorithmic mechanism design literature. The characterization can be regarded as an alternative approach to existing techniques to design truthful mechanisms. The construction of such mechanisms reduces to the construction of an algorithm satisfying certain “monotonicity” conditions which, for the case of verification, are much less stringent. In other words, verification makes the construction easier and the algorithm more efficient (both computationally and in terms of approximability).     

Low-randomness constant-round private XOR computations

In this paper we study the randomness complexity needed to distributively perform k XOR computations in a t-private way using constant-round protocols in the case in which the players are honest but curious. We show that the existence of a particular family of subsets allows the recycling of random bits for constant-round private protocols. More precisely, we show that after a 1-round initialization phase during which random bits are distributed among n players, it is possible to perform each of the k XOR computations using two rounds of communication. For , for any c < 1/2, we design a protocol that uses O(kt ²log n) random bits.     

Novel optoelectronic sensing system for thin polymer films glass transition investigation

The glass transition zone of thin polystyrene films on silica substrates has been investigated by using a novel optoelectronic integrated sensor involving simultaneous refractive index and temperature measurements. The sensor design is based on the deposition of thin polymer film by chemical dipping on the distal end of a standard silica optical fiber. Direct reflectometric interrogation and fiber-Bragg grating sensor integration have been used to simultaneously retrieve information about the refractive index variation over the glass transition region revealed by a temperature ramping. Sensor modeling and sensitivity have been investigated. The glass transition has been identified by measuring the change of the thermooptic coefficient in cooling down experiments. The comparison between refractive index transition and standard calorimetric analysis has been carried out to test the optoelectronic integrated sensor reliability. The proposed sensing system has demonstrated that it is able to measure the glass transition temperature of thin polymer films; moreover, the system and procedure can be readily implemented to investigate the effect of polymeric sample finite size and specific energetic interactions on the glass transition zone.