ABSTRACT
Elongated charged dust grains are ubiquitous in cosmic (Spitzer 1977, Harwit 1988) and laboratory plasmas (Chu and I 1994, Mohideen et al 1998, Rahman et al 2001). The formation of elongated charged dust grains is attributed to the coagulation of particulates in partially or fully ionized gases. Elongated charged grains can acquire rotational and spinning motions due to their interaction with photons and particles of the surrounding gas or due to the presence of an oscillating electric field in a plasma (Tskhakaya and Shukla 2001). In astrophysical objects the angular frequency of the dust grain rotation can reach a rather large value, namely between tens of kHz to MHz for thermal dust grains and hundreds and thousands of MHz for super-thermal grains (Spitzer 1977, Harwit 1988). Furthermore, recent laboratory experiments use cylindrical macroscopic grains in studies of ordered structures (Molotkov et al 2000) and levitation of micro-rods in the collisional sheath of an rf plasma (Annaratone et al 2001).
