Metal contacts to lowly doped Si and ultra thin SOI

We present our investigations on the fabrication of ohmic and Schottky contacts of several metals on lowly doped bulk Si and SOI wafers. Through this paper we evaluate the fabrication of rectifying devices in which no doping is intentionally introduced

Fabrication and characterization of the charge-plasma diode

We present a new lateral Schottky-based rectifier called the charge-plasma diode realized on ultrathin silicon-oninsulator. The device utilizes the workfunction difference between two metal contacts, palladium and erbium, and the silicon body. We demonstrate that the proposed device provides a low and constant reverse leakage-current density of about 1 fA/μm with ON/OFF current ratios of around 107 at 1-V forward bias and room temperature. In the forward mode, a current swing of 88 mV/dec is obtained, which is reduced to 68 mV/dec by back-gate biasing

Systematic TLM Measurements of NiSi and PtSi Specific Contact Resistance to n- and p-Type Si in a Broad Doping Range

We present the data on specific silicide-to-silicon contact resistance (ρc) obtained using optimized transmission-line model structures, processed for a broad range of various n- and p-type Si doping levels, with NiSi and PtSi as the silicides. These structures, despite being attractive candidates for embedding in the CMOS processes, have not been used for NiSi, which is the material of choice in modern technologies. In addition, no database for NiSi–silicon contact resistance exists, particularly for a broad range of doping levels. This letter provides such a database, using PtSi extensively studied earlier as a reference

Analysis of the entanglement between two individual atoms using global Raman rotations

Making use of the Rydberg blockade, we generate entanglement between two atoms individually trapped in two optical tweezers. In this paper we detail the analysis of the data and show that we can determine the amount of entanglement between the atoms in the presence of atom losses during the entangling sequence. Our model takes into account states outside the qubit basis and allows us to perform a partial reconstruction of the density matrix describing the two atom state. With this method we extract the amount of entanglement between pairs of atoms still trapped after the entangling sequence and measure the fidelity with respect to the expected Bell state. We find a fidelity $F_{\rm pairs} =0.74(7)$ for the 62% of atom pairs remaining in the traps at the end of the entangling sequence

Entanglement of two individual neutral atoms using Rydberg blockade

We report the generation of entanglement between two individual $^{87}$Rb atoms in hyperfine ground states $|F=1,M=1>$ and $|F=2,M=2>$ which are held in two optical tweezers separated by 4 $\mu$m. Our scheme relies on the Rydberg blockade effect which prevents the simultaneous excitation of the two atoms to a Rydberg state. The entangled state is generated in about 200 ns using pulsed two-photon excitation. We quantify the entanglement by applying global Raman rotations on both atoms. We measure that 61% of the initial pairs of atoms are still present at the end of the entangling sequence. These pairs are in the target entangled state with a fidelity of 0.75.Comment: text revised, with additional reference

Influence of local and remote white matter conductivity anisotropy for a thalamic source on EEG/MEG field and return current computation

nverse methods are used to reconstruct current sources in the human brain by means of Electroencephalogra- phy (EEG) and Magnetoencephalography (MEG) measure- ments of event related fields or epileptic seizures. There exists a persistent uncertainty regarding the influence of anisotropy of the white matter compartment on neural source reconstruc- tion. In this paper, we study the sensitivity to anisotropy of the EEG/MEG forward problem for a thalamic source in a high resolution finite element volume conductor. The influence of anisotropy on computed fields will be presented by both high resolution visualization of fields and return current flow and topography and magnitude error measures. We pay particular attention to the influence of local conductivity changes in the neighborhood of the source. The combination of simulation and visualization provides deep insight into the effect of white matter conductivity anisotropy. We found that for both EEG and MEG formulations, the local presence of electrical anisotropy in the tissue surroun- ding the source substantially compromised the forward field computation, and correspondingly, the inverse source recons- truction. The degree of error resulting from the uncompen- sated presence of tissue anisotropy depended strongly on the proximity of the anisotropy to the source; remote anisotropy had a much weaker influence than anisotropic tissue that included the source