SQM 2006: theory summary and perspectives

Abstract

In this write-up of my SQM 2006 Theory Summary talk I focus on a selection of key contributions which I consider to have a large impact on the current status of the field of strangeness physics or which may have the potential to significantly advance strangeness—or in general flavour physics—in the near future.

Hot electrons injection in carbon nanotubes under the influence of quasi-static ac-field

“…As the applied dc field (E) increases, the normalized current density (J) increases and reaches a maximum, and drops off, experiencing a negative differential conductivity (NDC) for both the zz-CNT and the ac-CNT as shown in figures 1a and 1b, respectively. The NDC is due to the increase in the collision rate of the energetic electrons with the lattice that induces large amplitude of oscillation in the lattice, which in-turn increases the electrons scattering rate that leads to the decrease in the current density at high dc field [37]. Similar effect was observed by Mensah,et.…”

“…Hence, strong enough axial injection of hot electrons in CNT under the influence of quasi-static ac field results in a switch from NDC to PDC leading to the suppression of the destructive electric domain instability, predicting a potential generation of terahertz radiations whose applications are relevance in current-day technology, industry, and research. Although similarly effect has been observed in the absence of quasistatic ac field [37], the differential conductivity (∂J/∂E) is higher and also hot electrons injection rate beyond which there is a switch from NDC to PDC represented by critical noneqilibrium parameter η c ) is lower in the presence of quasi-static ac-field than in the absence.…”

“…As the hot electrons injection rate increases, the peak of the current density decreases and shifts to the left (i.e., low dc fields). This is caused by the scattering effects due to electronphonon interactions as well as the increase in the direct hot electrons injection rate [36] [37]. The normalized current density (J) of the CNTs exhibits a linear monotonic dependence on the applied dc field (E) at weak field (i.e.,the region of ohmic conductivity) when frequency of ac field ω is much less than scattering frequency v (ω v or ωτ 1 i.e.…”

“…In this region, the hot electrons become the dominant determining factor [36]. The physical mechanism behind the switch from NDC to PDC is due to the interplay between the hot electrons pumping frequency (Q/n 0 ), which is a function of rate of hot electrons injection (Q), and the Bloch frequency (Ω), which depends on the dc field (E) [37]. At stronger dc field, the rate of scattering of the electrons by phonons is well pronounced resulting in the gradual decrease in the current density with increasing dc field (NDC region).…”

Parton rearrangement and fast thermalization in heavyion collisions at RHIC and LHC energies

“…Both are necessary conditions for the development of large elliptic flow. The description of various measured anisotropic flow patterns by hydrodynamic approaches (see, e.g., [12]) together with the scaling behavior of the elliptic flow with the number of constituents (see, e.g., [13,14]) well explained by parton recombination/coalescence approaches [15][16][17][18][19][20][21][22][23][24], give hints towards the partonic nature of the created matter which equilibrates very fast.…”